Samsung gets Tough
As noted Samsung’s wide angle camera is 108 MP, while the iPhone camera is 12 MP, and while the number of pixels is certainly important there are other factors that influence picture taking ability and quality, particularly the size of the aperture or f/stop. In this case they are similar in that the Samsung camera has a slightly smaller aperture, which means it is able to gather slightly les light, which the Apple camera has a slightly larger aperture. That said, they are close enough that they should make little difference on average, however the videos show a vast difference between the two. Of course, these videos are well selected by Samsung to show off the quality and ability of the Samsung camera system in the S21 Ultra, but they do it well. Ctl+Click to see the 15 sec. videos.
https://youtu.be/TZQSRQ53Sx8
https://youtu.be/j6fqaXPYg4g