8k is so fucking pointless.
have you seen 8k in person?
an increased resolution improves numerous aspects of game image quality, including AA, shimmering, textures, far object rendering, fine detail, etc.
and games are only getting more detailed, with larger maps and far distance rendering.
until AA can resolve these issues efficiently, resolution will continue to play a massive role in overall IQ.
first thing i did with a 4k TV was play dark souls 1 on it with a 4k internal resolution.
looked great, but then i changed it to an 8k internal res. and it was so much cleaner.
tried 12k and 16k internal res but it was an absolute slideshow on my PC at the time.
also once your display starts going over 100", you'll need 8k to maintain good PPI.