I share in that sentiment of being bored of how the gaming industry currently is, certainly compared to how it was in the past, but I don't think the push for realistic graphics is part of that issue. If anything, I think it used to be a much bigger issue, certainly in the 2000's when it was essentially common sense that a game was only worth your time if it was the most realistic thing made yet. To paint this picture a bit better, just do a quick search on google and these are the most notable games from last year vs. 20 years ago:
Looking at these first 13 games that show up, only 3 from 2002 weren't trying to push realistic graphics, whereas in the last year it's almost half the list. Sure there's a certain grey area here, in that Nier Replicant isn't going for realism today but if something like it was released in 2002, it would certainly be considered hyper realistic. Whereas Warcraft III looks super cartoony now but back then there was a big deal made out of the high-quality CG in its renders and cinematics.
Anyways it's pretty obvious if you've lived in both eras. Nowadays there's many indie games that become mainstream hits without realistic graphics and there is no shortage of non-realistic games being made by bigger companies and finding big audiences (Genshin Impact, Fortnite, Persona, many of those games in the image above too, I mean this goes on and on), whereas in the 2000's any game that looked colorful was widely dismissed as childish (Wind Waker, Mario, Nintendo in general really).
So there I disagree with your notion that the push for realism has gotten worse, because from what I see it's gotten a lot more controlled and games seem to have learned that you can push for realism while still having a distinct style - again taking it from that list, we can say GotG, Hitman and RE Village are all realistic games, but they look quite different from each other because they all have good art direction that suits their style. Back in the day it was kinda like, either you're doing hyper-realism or a cartoon for kids, no one seemed to understand art direction is a thing. I mean, there's a reason movies can look so different despite filming literally reality.
Anyways. I don't think the push for realism is hurting the creativity of games at all. Everything seems more stale than how it did in the 80's, 90's and 2000's, because of simple inevitability. The 80's and first half of the 90's was basically the birth of console games as we know them, developers were experimenting with a bunch of things because there was no precedent for what a game is. Thus we got all sorts of different games and styles. By the mid-90's, games were starting to settle into genres and you could start to see trends that were generally being followed by developers, but that didn't last long enough before 3D exploded into the scene and forced a new era of experimentation all over again, which again took roughly 10-15 years until the industry began understanding the patterns that work and settling down again.
I think it's inevitable for any industry to fall into these kinds of patterns once they get an understanding of what they're working with, these are big companies after all, they will always go in the direction of what is working best so they can maximize their profits. But beyond just the commercial side for them, I think to some extent we also benefit from this, as the best games in any genre tend to come when that genre is becoming more established and developers have a better notion of what worked vs. what doesn't (though at this point, that genre is usually overloaded with generic games that are just following trends and playing it safe).
Either way, I don't think realism has anything to do with it, it's just a thing that's normal to happen for the industry as a whole regardless of which art direction each game follows. What I will say though, is that the push for the most realistic graphics brings with it improvements for all types of games. 4K might be a term used to push realism but any game with any art direction will look better in a higher resolution, it's got nothing to do with realism. Ray-tracing exists because of this push for realism, but it can make all sorts of games look better, just look at any of those Minecraft ray-tracing videos. And even if a specific game isn't using any obvious "realistic" technology, there's all kinds of ways in which they benefit from the progress the industry makes a whole. One of the best examples here I'd say is Breath of the Wild, which takes full advantage of loads of a host of systems that existed to push realism in gaming, to make one of the best games ever while using a cel-shaded visual style. Hell, Breath of the Wild feels more realistic than most games on that list up there.