Probably an odd question as it pertains to myself specifically, but I thought maybe others here have had similar experiences and can tell me.
When I was a kid I used to really get immersed into the games I played; I'd feel as though I was actually, feeling the very walls around me in dungeon crawlers, getting tense in fights and such, but nowadays I don't really get that sense any more. I'm in my mid-30's and now I'm thankfully able to afford any game I wish, I thankfully can choose how long I spend gaming, yet I just can't get immersed, I just can't get pulled in anymore.
My buddy told me about the Witcher 3 and told me it's great and immersive like only the oldest games ever were, and yet when I played it....I got kind of bored, and lost interest somewhat fast. One possibility is that maybe with modern proliferation of game knowledge, we can simply google for anything we want rather than let the game help us find what we need, pulling us out for that much of the game, another possibility is that we recognize mechanics and animations for what they are, and we try and memorize enemy combat animations, and our own iframes and such, even if instinctively.
I honestly can't remember the last game I played where I got immersed into the game and just felt the world rather than just see it.
You can get escapism fatigue just like with anything else.
Like you mentioned, sometimes you start to notice the formula and it prevents immersion. Oh, cool, this is the 300th Zelda clone and the Big Bad is named Gornandork. You might as well just play Zelda again.
There is also an aspect that is exposure and analysis. As a kid, the death of the author is usually a given. A story isn't a human coming up with something on the spot, it's a universe to learn about. Eventually, you realize that the Zelda story (again) isn't some carefully-designed lore or great work of fiction or a consistent world at all, it's just a games company trying to make as much money as possible by paying people to write a story that seems interesting but doesn't deviate too far from the formula. This kills some of the magic, as now you're a critic: rather than a revelation or joy, you see the soulless cash-grab, the (low) worth of the story to those involved, the pointlessness of it. You start to want more, as it will take more than lazy corporate riffing for you to get swept away, whereas before it was novel enough (to you) that you didn't notice. Pokemon is a pretty good example. It was never a great story, mostly a way to sell toys, but it printed money so they just do the same thing over and over and over again. I can't imagine the dryness of trying to follow the full story of the main series.
You might just want novelty, or even just (comparatively) good writing. Or you might need a break from the medium, find something with different tropes, or even just do something that isn't escapism but scratches a similar itch of distraction, obsession, entertainment, enjoyment. Sports, hiking, irl bar games, taking really good naps, making really good food, organizing your living space and life, and especially anything social that you enjoy.
Also you might just want to make a post that asks for non-samey video game recommendations, ha.