I mostly play Nintendo games so it's kind of hard to be a graphics snob.
But look at something like Metroid Prime, which came out for GameCube in 2003. Something with comparable graphics could be released as an eShop game for Switch today by some studio with a $500k budget. And really, the game looks fine. We've kind of reached the peak graphics threshold, and honestly we reached it a while ago. It's just a matter of cost and ease now.
Honestly, frame rate is a bigger deal to me than resolution. If it runs smooth I don't really care how many pixels they jam in there. Something like Breath of the Wild looks better to me than some grimdark hyper realistic dual-core engine bull**** that keeps getting pumped out by third parties.
And tbh, BioShock was very good but it got REALLY overhyped. It was kind of a more mainstream version of some serious mid-90's shooters like System Shock, Deus Ex, and Half-Life. A bit more challenging, atmospheric, cinematic, and a good old fashioned twist. In 2006 that was a big deal, because there was really nothing like that from mainstream big budget studios. And it was a very good game, I enjoyed it a lot. But I see these lists calling it a game that defined a decade, or the most influential game ever, or a top-5 games of all time, and I just have to shake my head. BioShock was a very cool shooter but it was hardly the first or best game to do what it did. No offense and I don't mean to sound like an elitist, but it's very easy to tell who had experience with "real" FPS games prior to BioShock, and who had only played mainstream matchmaking games like Halo or Counter-strike.