I dislike the notion of this thread, if I'm being honest, and I almost refrained from posting in it. But so long as we can respect that one member's "most overrated game" can be another member's "best game ever" and that there's nothing wrong with that, I suppose I'll offer up a short list of highly-regarded games I've tried that, for one reason or another, haven't worked for me at all.
Minecraft
This game is a great teaching tool for kids and objectively speaking the works of art folks have built with it over the years are truly impressive. But building games do nothing for me and good Clarke is this one ugly.
Metal Gear Rising: Revengeance
The cutscenes are too brief. The story skips plenty of beats that ought to have been shown rather than told. The soundtrack isn't to my taste. Technical action games in general aren't my gig. There's pretty much nothing about this game that does it for me and overlaying it with a Metal Gear mesh wasn't enough for me not to return my purchase.
Grand Theft Auto V
I'm glad I watched my friend play this rather than played it myself. The only thing about Grand Theft Auto gameplay that I find enjoyable is driving around recklessly. Nothing else clicks. I'll grant that the script had something akin to wit to it from time to time but the Trevor character in particular is such an affront to my senses that I rolled my eyes dozens, if not hundreds, of times. Compounding issues is the fact that crime stories almost never interest me to begin with.
Yoshi's Island
Egads, I know there's a good game in here but the baby mechanic slaughters it for me.
Fortnite
You can toss in any other battle royale game here if you wish because I can virtually guarantee you I wouldn't like them either. I gave Fortnite the old college try, but I dislike virtually every online multiplayer game to begin with so the odds weren't exactly in my favor. Spoilers: nothing about that changed here and I uninstalled the game within a week.
Dead By Daylight
More like bored by daylight.
Tetris
I can't make it more than five minutes with this one. Not because I'm terrible at it (I'm not exactly great but I'm alright) but because it bores me to tears. If ever I am detained somewhere, my captors will surely break me like an egg if I am to be subjected to Tetris.
Final Fantasy VI
Unlike the rest of these entries, I actually really like Final Fantasy VI. The thing is, I disagree empirically every time I see someone say "aaaactually, the REAL best Final Fantasy is VI..." I dislike the game's magic-learning system, I find its characters on the whole less fleshed-out than plenty of characters in most of the Final Fantasies that followed it, the frequency of "a character in your party just said something, but due to the freedom of party selection afforded to you, we cannot tell you who!" bothers me a bit, and some (though not all!) of the "charming, goofy" moments the game is so lauded for just fall completely flat for me. Like I said, I really like this game. But nowhere near as much as some.
Undertale
I liked it... OK, but the bullet hell is obnoxious (it doesn't help that I'm bad at it) and I've been far more emotionally impacted by many other games I've played. Which is probably worth noting given how some of Undertale's fandom touts this game as the one truly emotional experience this gen or whatever. The final boss on the neutral path is the closest I've come to throwing my controller at the TV in... well, in history, really.