My first dedicated gaming system was the PS1, and in general I have no trouble going back to the sprites and chunky polygons of the mid-to-late 90s, whether on consoles or computers
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as long as I can upscale them to 1080P
Beyond that it gets a bit hit and miss- SNES and Mega Drive games look and sound fine to me and I’ve played plenty of 16 bit console games as an adult. On PC, I can enjoy 2D stuff like Sam & Max Hit the Road or the original X-Com but most early 3D, like the original System Shock, looks a bit too much like visual vomit.
Going to 8-bit, while the vast majority of NES games are too primitive to my eyes and ears, I have no problems with Game Boy/Game Boy Color games.
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(Well, at least the good ones, mostly made by Nintendo)
Is it just nostalgia because I had a GBC as a kid or is it because Game Boy games came later and had more developed visual aesthetics? 
My limit is probably the very late 80s
Chaplin made silent movies long after the sound film had been invented. He was very vocal about his dislike of “talkies” and saw them as . Chaplin saw in silent cinema absolutely no limitation that’d have prevented him from making the films he wanted to make. While adding sound to films seems like obvious progress to us nowadays, it also further diluted what made movies unique compared to other artforms. There’s no reason to think we couldn’t have had a hundred years of incredible, inventive and still surprising silent films. Books haven’t changed in thousands of years and they haven’t started repeating themselves yet.
Technical and artistic progress aren’t connected in any straightforward manner. The topic of course gets quite a bit more complex for videogames since they are so deeply interlinked with consumer technology and are more directly interactive than other media, but the vast majority of videogames made today could have been made twenty years ago as well. The actual reason people usually don’t play older games is because the one thing that we’ve actually seen undoubtable progress in is that games have gotten much more effective at keeping your dopamine receptors firing. If you grew up playing ubisoft games or mobile gacha bullshit you’ll find it very hard to enjoy games that might delay gratification at all (be it through deliberate means like difficulty or non-deliberate like bad tutorials).