Apple (AAPL) has changed its healthcare focus from a meager “Project Quartz” to a more meaningful and robust “Project Mulberry”, including AI agents to collect and process the data that Apple devices collect about you.  This is not the ‘secret stuff’ brands collect, like what OS you are using, what device you are on, your search results (if you let them), and almost everything about what you have bought[1], but more the data that you allow Apple to collect by using the Apple watch, your iPhone, your AirPods, and even some 3rd party applications.  This is ‘health’ data, that includes sleep patterns, steps, calories, heart rate, weight, and a variety of other metrics about your bodily functions.
The objective is to provide Apple users with information that will make them healthier and more fit, but Apple, even before the platform is available, has made the upgrade to AI agents and an integration with Apple Intelligence, to make that information more ‘real-time’, personal, and meaningful.  The agents are the scavengers that will poll your Apple devices for the health information they collect and bring it to Apple Intelligence for monitoring and evaluation.  It is thought that Apple will not only offer you evaluations of your nutritional and sleep habits but could even offer camera-based assessments of your workouts and access to educational videos, put together by internal and external health experts. 
While the range of detail is thought to delve into physical therapy, mental health, and even cardiology, the initial focus is thought to be nutritional, with monitoring and alerts leading to personalized health advice based on your data, although there has been talk of AI-based mental health counseling and chronic disease predictive analysis.  As one might expect, Apple’s focus seems to be on the ‘user experience’, the part of the Apple persona that allows them to charge a premium for their products, but Apple is certainly not the first to go in this direction in this new age of AI.  Google’s  (GOOG) Fit is a similar collector of personal health data through Android’s Health Connect.  This platform allows permitted 3rd party apps to supply and collect data that feed the Google Fit app, but is more a collector, aggregator, and visualizer than an advice tool, although Google is currently working to integrate that data into its other health related services, with a tie-in to reference ‘reputable sources’ on YouTube.
Amazon (AMZN) also has a health program, but its focus is more oriented toward B2B with the Amazon Pharmacy supplying information on medications and interactions and the Amazon Clinic and One Medical able to set up virtual video or text sessions with clinicians (some on staff) that can evaluate conditions, make diagnoses, and prescribe medication for relatively common illnesses.  There are also companies like Noom (pvt) or MyFitnessPal (pvt) that are more specific to food and calorie management but given the enthusiasm for Ai that seems rampant across the health sector, we expect almost every health related application to leverage AI to stay competitive.
There are a few caveats here, particularly HIPAA regulations which regulate any health information that is maintained or transferred.  Entities involved must encrypt health data, limit access, perform risk assessment, maintain audit trails, breach notifications, and take ‘reasonable steps’ to prevent access to or disclosure of patient information.  HIPAA is difficult enough to understand and maintain, but adding AI to the mix opens everything up to new legal questions, many of which have yet to reach the courts and as liability becomes a potential issue when health-related advice is being given, we expect many new court cases that will not only focus on the potential liability of poor or incorrect data, but will include questions of algorithmic bias, inadequate software testing, and the fact that Ai systems are essentially ‘black boxes’ that make it impossible to derive where or how an AI arrived at a particular diagnosis or conclusion. 
Smart lawyers will not only include site owners but also those who wrote the algos that run them, looking for biases that could cause hallucinations, errors in judgement, or flawed diagnoses based on poor human vetting.  When Ai developers are called into court to defend issues like what data was included in an AI’s training or what process was used to draw a conclusion, high level math will not be how they are judged by a jury, so while Apple jumps into the fray to provide a positive health experience through Project Mulberry and Apple Intelligence, its not like Wikipedia, where you take things with a grain of salt.  Healthcare decisions affect people’s lives, as some can be significantly influenced by the information given by Ai healthcare.  There are good and bad doctors, and sometimes doctors make mistakes, which is why malpractice insurance exists, but will there be malpractice insurance for an application that gives incorrect advice or misdiagnoses an ailment or mental condition?


[1] IP Address
Device Type & Model
Operating System
Device Identifiers (trackers like AAID, IMEI
Screen Resolution
Installed apps (some)
Browser type & version
Cookies (optional)
Browsing History (Optional)
Location Data (Optional)
Referring websites
App usage
Contacts & Calendar (Optional)
Photos & Videos (Optional)
In-app purchases
Search queries (Optional)
Social Media Activity
Shopping activity
Form submissions
Wi-Fi network name
Data usage
Bluetooth data
Sensor tracking
Accelerometer & Gyroscope data
Ambient Lighting data
‘like’ data
DNS lookups
…To name a few.

​We have mentioned that the EU has implemented a set of power usage restrictions on CE products that will essentially ban the sale of 8K and Micro-LED TVs in the EU.  The European Commission seems to have rejected requests to review the ruling, which is to go into effect on March 1, 2023, which leaves little time for TV brands and other affected parties to make their case, with the commission seemingly unmoved by an such pleadings thus far.  That said, TV brands are a creative lot and rarely do they decide to acquiesce to regulations without a fight, so there are those in the industry that expect TV brands to adopt a few ‘new’ tactics to allow them to meet the new regulations without inventing new technology.
The Eu regulations are based on power consumption, and in that *K TVs have 4 times the number of pixels to process for each frame, they do not meet the tighter power consumption limits, with Micro-LED TVs having similar power issues.  However, when TVs are sold, the sets are typically set for the highest brightness settings to make them look as they did on the floor of the retailer (retailers always set demo sets to their ‘highest’ settings), which also sets power consumption to its highest levels.  The Eu regulations specify that the power consumption of a set is measured as the set is taken ‘out-of-the-box’, so TV brands will likely change the default brightness settings for those 8K sets to be sold in the EU, to their lowest settings, allowing them to meet the new regulations.  This might not sit well with consumers, who could be disappointed with the brightness being diminished relative to the store demo, but brands can make sure that a notification is made to EU consumers as to the setting and how to return it to the higher brightness once the set is brought home.
Of course this defeats the purpose of the EU rule, which is to lower overall power consumption, but that would likely mean little to brands that continue to build and promote 8K and Micro-LED TVs.  Brands also have another route, and that is to remove the tuner that is available in TV sets, lowering the power consumption and essentially turning them into monitors.  The tuner is the device that allows the TV  to be connected to an over-the-air antenna, and while only ~30% of TV owners receive such signals, it’s a large enough percentage that it might cause those potential 8K TV customers to stick with their old TVs, although 70% of owners, those using set-top boxes or streaming systems, would not be affected.
There is an even more subtle reason why removing the tuner for EU customers is an iffy solution to the 8k dilemma, and that is that many retailers have monitors and TVs in separate product and profitability categories, with TVs the higher margin product.  If the tuner is removed from a TV, it become questionable as to what category it falls in and whether the margins should be at the TV tier or the lower monitor tier, and retailers are typically not willing to allow those margins to change, which makes the ‘brightness’ scheme the more likely in the near-term.
We do understand the EU’s objective, and TV brands typically do not promote devices on the merits of their low power consumption, so little work toward reducing power is done unless it becomes a talking point or is the subject of new regulations, as will be the case in March.  The one thing we are sure of is that if TV set brands see 8K or Micro-LED customers in the EU, they will find a way to meet or beat the new regulations.
 

​We have mentioned that the EU has implemented a set of power usage restrictions on CE products that will essentially ban the sale of 8K and Micro-LED TVs in the EU.  The European Commission seems to have rejected requests to review the ruling, which is to go into effect on March 1, 2023, which leaves little time for TV brands and other affected parties to make their case, with the commission seemingly unmoved by an such pleadings thus far.  That said, TV brands are a creative lot and rarely do they decide to acquiesce to regulations without a fight, so there are those in the industry that expect TV brands to adopt a few ‘new’ tactics to allow them to meet the new regulations without inventing new technology.
The Eu regulations are based on power consumption, and in that *K TVs have 4 times the number of pixels to process for each frame, they do not meet the tighter power consumption limits, with Micro-LED TVs having similar power issues.  However, when TVs are sold, the sets are typically set for the highest brightness settings to make them look as they did on the floor of the retailer (retailers always set demo sets to their ‘highest’ settings), which also sets power consumption to its highest levels.  The Eu regulations specify that the power consumption of a set is measured as the set is taken ‘out-of-the-box’, so TV brands will likely change the default brightness settings for those 8K sets to be sold in the EU, to their lowest settings, allowing them to meet the new regulations.  This might not sit well with consumers, who could be disappointed with the brightness being diminished relative to the store demo, but brands can make sure that a notification is made to EU consumers as to the setting and how to return it to the higher brightness once the set is brought home.
Of course this defeats the purpose of the EU rule, which is to lower overall power consumption, but that would likely mean little to brands that continue to build and promote 8K and Micro-LED TVs.  Brands also have another route, and that is to remove the tuner that is available in TV sets, lowering the power consumption and essentially turning them into monitors.  The tuner is the device that allows the TV  to be connected to an over-the-air antenna, and while only ~30% of TV owners receive such signals, it’s a large enough percentage that it might cause those potential 8K TV customers to stick with their old TVs, although 70% of owners, those using set-top boxes or streaming systems, would not be affected.
There is an even more subtle reason why removing the tuner for EU customers is an iffy solution to the 8k dilemma, and that is that many retailers have monitors and TVs in separate product and profitability categories, with TVs the higher margin product.  If the tuner is removed from a TV, it become questionable as to what category it falls in and whether the margins should be at the TV tier or the lower monitor tier, and retailers are typically not willing to allow those margins to change, which makes the ‘brightness’ scheme the more likely in the near-term.
We do understand the EU’s objective, and TV brands typically do not promote devices on the merits of their low power consumption, so little work toward reducing power is done unless it becomes a talking point or is the subject of new regulations, as will be the case in March.  The one thing we are sure of is that if TV set brands see 8K or Micro-LED customers in the EU, they will find a way to meet or beat the new regulations.

In September we noted that new regulations in the EU, would forbid the sale of 8K and micro-KED TVs.  The rules are not specifically targeting 8K or micro-LED TVs but set power consumption requirements that are based on the energy efficiency (EEI) of the device in order to improve the ecological and environmental impact of television usage in the EU.  Based on a 2016 study, the Eu concluded that the energy consumption from such devices was 3% of the region’s total energy consumption, and that would grow (including monitors and digital signage) to nearly 100 TWh per year by 2030, or roughly 5 times the output of the Grand Coulee Dam in Washington, that services over 8m people in Arizona, Southern California, and Southern Nevada.
The regulation excludes projectors, medical displays, white boards, digital signage, and VR, and set the EEI based on a compilation of the power requirements of HD and UHD (4K) sets available between 2012 and 2017.  They applied those findings to the higher resolution of 8K, however there is a problem with that logic.  The pixel density of an 8K set is 2X that of a 4X set, meaning twice as many pixels must take up the same space, forcing each pixel to be smaller.  Each sub-pixel is surrounded by a black mask that keeps light from reaching the driving electronic (which would cause transistors to stop functioning), however, the electronics that drive each sub-pixel (red, green, and blue) are basically the same size as those in 4K sets, as the same display backplane production infrastructure is used for both 4K and 8K sets.  This means that the black mask for 8K pixels takes up more of the pixel and reduces each pixels’s brightness.  In order to compensate, and make the 8K TV and bright as a 4K TV, the backlight must be brighter, which means it consumes more power.
No current 8K or micro-LED TV sets meet these requirements, and 8K proponents were hoping that the EU would meet again before the end of this year and revise the regulations.  Unfortunately such a meeting has not been scheduled, which leaves only a few months next year for such a meeting, which, if held, might come to the same decision.  As western Europe is only 16% smaller in terms of the sale of advanced (4K and 8K) TVs, even though the 8K market is still a small part of the overall advanced TV segment, it will have an impact on the plans of TV set brands until the issue is resolved.  Creating the infrastructure to reduce the size of the electronics for 8K sets is likely a non-starter for most brands, so there seems to be no near-term alternative unless 8K advocates are able to convince the EU commission to postpone or change the new rules, if they can even get a meeting, so if you live in the EU and you are desperate for an 8K set, you have util March 31 to grab one…

If new rules in the UK are not changed, starting in March of next year 8K and Micro-LED TVs will no longer be available to consumers in the EU.  A series of energy-related rules will come into effect next year that set energy use requirements for televisions with more than UHD resolution (8K) and micro-LED based displays as part of a larger ‘ecodesign requirement for energy related products’ program initiated in 2019.  When the guidelines were determined, 8K television sets were barely a notion, other than as demos at trade shows, so the specs were written (pre-2019 release) before there were a reasonable number of 8K sets available on which to make typical efficiency and power consumption calculations.  The 2023 rules require that 8K television sets must consume the same amount of power as 4K sets or would be unable to be sold in the EU.
Based on a quick check of Mini-LED/QD and OLED TVs, 8K TVs consume 90% more power than their 4K equivalents, with 8K OLED TVs coming in at ~77% higher and the 8K Mini-LED/QD sets coming in ~102% above their 4K counterparts.  A further look by the 8K Association, a group with an obviously big stake in the debate, has indicated that they find that no 8K television sets currently in the market would meet the new specifications.  The regulatory committee that has set the guidelines is supposed to meet before the end of this year to review the guidelines, although no meetings have been scheduled to date.
The problems facing 8K TV power requirements is simple to understand.  8K TVs have to fit 4 times as many pixels into the same space as 4K TVs, which means each pixel has to be smaller.  As the electronics that control each pixel remains basically the same size in both 4K and 8K, the area available for the backlight to pass through becomes smaller as a percentage of area in 8K pixels.  In order to compensate for the lower amount of light, the backlight in 8K sets needs to be brighter and therefore requires more power.  Additionally, given the increased number of pixels in 8K sets, the processing done for each pixel is also multiplied by 4, requiring more transistors and more power to drive them.
Those in the 8K ecosystem stand against the new regulations citing the effects on EU consumers who will no longer be able to avail themselves of the latest 8K content and will ‘fall behind’ other regions, although we are hard pressed to find a regional competition toward establishing 8K as the day-to-day television media format.  Japan has the only (state-sponsored) 8K broadcast station, usually reserved for important events, travelogues, and nature specials, and while there are streaming services that supply 8K content, 8K TV sales have not been stellar, with ~350,000 8K sets sold last year, a less than 1% share of the TV market, and Samsung Electronics (005930.KS) holding a ~65% share.
While we understand both sides of the 8K argument, the broadcast industry is still grappling with 4K while some streaming services charge extra for 4K, so pushing the television industry toward reducing power requirements for 8K TV does not strike us as a bad idea, although one that has relatively little relevance to consumers at least currently.  At some time in the future 8K will become germane to the industry but pressing the industry over a product that was developed way before it became useful to consumers will serve to push set producers to improve 8K set power consumption or abandon the product until there is at least some consumer demand.  We doubt there will be much consumer lament over ‘falling behind’ other regions in the world of television technology…

Way back in 2007 SMPTE (Society of Motion Picture & Television Engineers) began to set standards for what is known as 8K resolution, a format that the Japanese Public Broadcasting system began to research in the mid 1990’s to help Japanese CE companies maintain a leading share as LCD TVs began to become popularized.  Sharp (6753.JP) released an 85” 8K LCD TV at the 2012 CES show, soon to be followed by Panasonic’s (6752.JP) 145” 8K Plasma demo at IFA in the same year, and the 2014 Winter Olympics and the World Cup were broadcast in 8K.  By 2018, while forecasters were relatively conservative, predictions that 8K would be ‘mainstream’ by 2023 and would sell over 11m units were appearing along with 8K sets from almost all major TV brands and in 2020 Samsung Electronics (005930.KS) noted that the Samsung Galaxy S20 smartphone would be able to record in 8K, although it required 600MB/minute of storage capacity.
But things have not been going well for 8K recently, despite the support from TV set manufacturers, who generate premium prices for a resolution that is 4 times the resolution of the 4K TVs that are becoming the standard globally, as US TV brand Vizio (VZIO) has decided to drop the format from its TV lineup and rumors that early 8K cheerleader Samsung might be cutting back on offerings going forward, although we expect they will maintain some 8K representation in the Mini-LED/QD lines.  But it gets worse in that OMDIA has just cut its 8K forecast again, after cutting it late last year, as it seems that less 8K TVs were shipped in 2021 than in the previous year, with Samsung, the share leader at ~65% seeing 18% less units y/y.  The latest cut puts the number of global 8K households at 2.7m by 2026, down from 9m by 2025 in last year’s forecast (here are 596.97m households in just the top 10 largest countries), only 0.15% of all TV sets shipped last year.
Of course there is the fact that there is very little native 8K content, which would be the real reason for owning an 8K set, and a distrust of upscaling techniques that have always been sold to the public as ‘enhanced’ versions of 4K content (see sidebar), but it has always been our view that buying an 8K set to ‘anticipate’ content would cause one to own an outmoded set when that content finally comes around.  Those issues, along with the significant expense broadcasters would have to incur to air 8K content (Streaming services can but it takes considerable bandwidth even with compression), seem to have put a real dent in 8K, at least for the time being, and adding the difficult macro environment seems to have tapped off any residual COVID-19 related consumer interest.  Now it is up to TV brands, who will be looking to rein in costs, whether they can support an 8K format with such small unit volumes in such an environment, but we expect 8K will be back again when consumers are less burdened by inflation and TV set brands can try to squeeze out that extra bit of margin on 8K product once again.

Most 8k upscalers fill in the missing pixels by interpolating image content around the target pixels.  If there is consistency, such as a red background, the system will assume that it can fill in the extra pixels with that color, but when it comes to fine detail, each upscaler has to use its algorithm to make a determination of what would look best and place that image on the additional pixels.  AI techniques can be used to better understand an image based on what the system has seen in the past, but all upscalers make assumptions as to what ‘might have been there if it was taken by an 8K camera’.  TV set brands and retailers will show you a 4K and an 8K set next to each other to point out the skill of the upscaler, but most of the difference is actually the number of pixels on an 8K set displaying a higher resolution image, as no upscaler can create ‘better’ images than were captured natively, they can only attempt to fill in the blanks with something close.
​

8K TVs are a difficult sell to consumers and rightly so as there is little 8K content that would allow consumers to take advantage of the increase in resolution that 8K TV sets provide.  However each year TV brands offer the public 8K sets, promising that they will be able to watch their favorite 4K (or less) programs using the upscalers built into 8K sets, while waiting for the world to catch up to 8K broadcast and content standards.  The problem is that by the time there is enough 8K content to make a difference to TV purists, the 8K set you just purchased will be either outdated or unable to display the then current content, which would cause considerable consternation from past purchasers.
There are lots of reasons why 8K broadcast content is not available (other than in Japan in limited quantities), but the bottom line is cost for broadcasters and bandwidth for streaming services, so unless you are satisfied with watching a few travelogues and animals in the wild, 8K TV set purchases should be put on the back burner.  We have watched a continual decline in 8K set unit volume estimates over the last year, although brands themselves don’t seem willing to make an estimates of where the 8K TV set market will be over the next few years, so we have put together an aggregation of those estimates we have found, excluding those that we know have been updated during recent reality checks.  We note that assuming a steady-state 220m TV sets sold each year shows that even the most aggressive estimates in 2025 show a penetration rate below 2%, so we would not be expecting TV brands to be adding significant 8K capacity, other than as demo units or for sales to China where 8K seems to be growing the fastest, but with Samsun owning some 65% of the 8K TV market recently, there js little left for others and producing such 8K sets in small quantities is a costly process.  Here are the aggregated estimates:

​OK, you did it, you bought an 8K TV despite the fact that there is little native 8K content to watch.  The salesman was quite good at describing how ‘smart’ the TV was, taking your mundane 4K content and amping it up to 8K, and he was also convincing with the story that you want to be ready when native 8K content becomes available, so you won’t have to rush out with all of the other luddites to buy an 8K TV.  Of course, he did not indicate that you cannot ‘create’ new image information when viewing a 4K image on an 8K TV, you can only duplicate more of what is already there, so you gain the ability to sit closer to the TV without seeing individual pixels, and little else.
But vindication is coming! Or at least it is for those who have purchased the TCL (000100.CH) Series 6 ROKU (ROKU) 8K TV , a 65” model that sells for ~$2,000, as TCL will soon begin to offer a native 8K subscription streaming service, giving you a break from those YouTube (GOOG) clips that you use to show buddies how cool your 8K TV is.  The content is part of a collection from The Explorers Foundation, an non-profit organization devoted to raising awareness of the challenges and issues associated with the preservation of the planet’s heritage through conservation and research.  This means you will eventually have access to 8K content from such projects as “American Crocodiles in Jamaica”, “Scarlet Macaw in Honduras”, or “Lemurs in Vohimana” (Protected Rainforest in Madagascar).
As big fans of nature content, we are certainly all for such access, even if we are still relegated to 4K, but while those who have actually purchased 8K TVs might have an interest in such content, we expect they are looking for a bit more than nature footage and the infrastructure for native 8K streaming is not available for broadcast.  You will have to be satisfied with those YouTube clips and a few 8K movies that have to be compressed in order to pass them through your fiber and Wi-Fi.  It is still a struggle to justify 8K TV, and will likely remain so through 2022, despite the offerings from CE companies looking to score in the category, so hold on for another year and watch any native 8K you can.  No information on the cost or the date when the 8K service will begin but the Explorer’s app is free.

​While 8K TVs are already part of the CE landscape, we have not been big fans.  Not because we don’t like the idea of higher resolution TV but because the average consumer is buying something that will cost more but have relatively little incremental value.  8K set producers will explain how your 8K TV will have 33.18m pixels while your 4K set has a mere 8.29m but they don’t mention that you will not see much of an advantage with an 8K unless you are sitting relatively close to the screen, which in most cases is uncomfortably close.  There is ‘upscaling’, the process by which your TV takes lower resolution content and scales it to utilize those extra pixels., so, according to salesmen, your ‘up-scaled’ content will look better on your 8K TV.  Unfortunately this is not true, as it is impossible to increase the resolution of content to a point higher than what it was shot in, so up-scalers find ways to take the content and just spread it out among more pixels, and as above, those extra pixels are only going to make a difference if you are close to the TV, so the idea that upscaling low resolution content to 8K is going to make it look better is technically incorrect.
So what are 8K TV sets really good for?  Displaying 8K content.  Any 8K content will look  sharper on an 8K TV set, although much of the difference will be lost if you sit a normal distance from the TV, but when it comes to native 8K content, there will be nothing better than an 8K TV.  That said, the gist of our view on 8K TVs is that 8K content is still quite rare, with the few sources, primarily OTT streaming services, with only one broadcast network, the BS8K system in Japan, which is run by NHK (state) and shares its channel with the channels 4K service.  The 8K service is available in Japan and will be the source for 8K programming from the upcoming Olympics, but is relatively limited in its offerings, which tend to be travelogues and a few movies (West Side Story just added) that were shot in native 8K.  Other than that, the rest are OTT services with YouTube (GOOG) being the biggest, offering a variety of travel and exploration 8K content and a few movies, NASA’s 8K channel, France’s The Explorers Channel (VSAT), and an 8K channel from Rakuten (4755.JP), and while some game consoles sort of offer 8K resolution output, there are only a handful of games that support 8K rendering.
All in, things are only slightly different for 8K than last year, and that is mostly the fact that some smartphones can actually record in 8K, but in most cases those are able to record relatively short (3min – 5min) clips and there is little 8K editing software that would allow you to make any changes, but what about Blu-ray?  If we are talking about raw 8K footage, meaning uncompressed, it takes 121.5 Gb/minute of capacity, so a 1 hour movie would take up 7.3 terabytes of disc space, and since  a Blu-ray 3.0 disc only has the capacity for 100Gb, raw 8K is currently impossible.  This means that some form of compression would be needed, and likely quite a bit to fit into that space requirement, so you are then losing the high resolution of 8K even before it gets to your TV set.  The good news is that many movies are shot in 8K even though the release is at best 4K, which allows the producer and editor the option of blowing up a portion of a scene without losing too much detail, so when 8K storage and streaming issues are finally resolved, many films will be able to be released in 8K format, but by then 8K TV technology will have also improved, so the issue is why buy one today?  The answer is the same as it was the last time we reviewed the status of 8K…wait.

​Whether we want it or not, 8K is here.  Panel producers and TV brands will be jumping at the opportunity to squeeze premium out of the TV market for the holidays and the next few years with the promotion of 8K TVs, especially as we approach the 2020 Olympics in Japan (July 24, 2020), where portions of the programs will be broadcast in 8K over the Japanese NHK network.  That said, why would you want to buy an 8K TV?  Are they so much better than 4K and HD TVs that they are worth the astronomical premiums that are (and will be) charged for 8K in the near-term.

​There is almost no native 8K content available other than a few YouTube, NASA, and travel shorts.  As we have noted, there will be some 8K content available  during the 2020 Olympics in Tokyo, but the content space, especially broadcast content is still gearing up for native 4K content.  So other than the story that you are buying a TV that will be around for many years, what might be suggested by retailers and brands as a reason for buying an 8K TV?  Simply put, “upscaling”
Upscaling is the process for taking lower resolution video content and ‘expanding’ it to fill higher resolution displays and 8K TVs put that process to the test more than any so far.  To understand what is actually happening, we offer this table of resolutions:

​Each of these calculations is based on a 75” TV screen, which means if content is developed in HD and shown on an HD screen, the actual image will fill each pixel.  If it is shown on an FHD screen, there will be no information ~10 pixel in each inch, and if it is shown on an 8K TV, there will be no information for ~83% of the pixels/inch.  Does this mean that you see lots of blank spots when HD content is played on larger resolution screens?  No, because TV engineers have created upscaling engines that fill in those blanks and give you a full picture.  There is a hitch however, and that is the law that says you cannot ‘create’ image data if it was not there in the first place, so display engineers came up with some solutions that sort of ‘fill in the blanks’.
In the most simplistic forms, simple upscalers take the video information from a single HD pixel and create duplicate pixels (with the identical information).  Upscaling from HD to UHD requires each HD pixel to be duplicated eight time, creating a 9 pixel block from just one.  It’s a great idea, but results in lots of duplicate information that creates jagged lines and some messy looking images.  Who looks at HD content these days anyway?  You do, as much news content is HD based, but using that methodology when you need to fill 8K resolution screens would be (and is) almost impossible to view.  Other methods for creating those missing pixels get more complex, some taking information from a number of pixels around the subject pixel, while some check for ‘noise’ or individual pixel data that might be distorted to avoid duplicating the inaccurate information.  With the advent of faster processors, upscaling techniques have become more sophisticated with many brands designing their own scalers as a selling point.
Current upscalers combine adjacent data with information from the same pixel location in both previous and forward frames to get a better understanding of what is actually happening to the image on an other than single moment in time, and of course, artificial intelligence and machine learning have nw become the mantra for upscaling algorithms and hardware.  That said, there is only so much even the best upscaler can do, as the information it has available is limited to the contents original format, so the ‘magic’ that TV brands extol in 8K sets, that are said to make content look better than the original is quite iffy. 
There are certainly more pixels/in. in an equivalent 8K TV, and native 8K content will look spectacular on an 8K set, but the difference between what 4K content would look like on a 4K set and what it would look like on an 8K set is so minimal that many hardware reviewers find it difficult to see the difference.  When you bring that down to the average consumer, it would be hard to convince a buyer that he or she is going to see an immediate improvement in day-to-day video content.  All in it means that consumers have years before they have a reason to buy an 8K TV  and by then we suspect there will be little premium to pay.