Or people who argued that “the eye can’t see more than 60fps”
A common video subsampling setup is 4:2:0.
https://en.wikipedia.org/wiki/Chroma_subsampling
In addition, common video compression techniques (at least the simple ones that I could still understand) basically reconstruct blocks of pixels. Reconstruction is lossy, at best.
If I had to guess, something similar could be done in games as part of their optimizations.
For 83" TVs you obviously need more pixels to get a good viewing experience because you don't position yourself several meters in front of the screen to make the pixels unnoticable.