Kingdom Come:Deliverance. I started playing when in had a 1080ti and got pretty far, then I tried to upgrade to an AMD 6900xt. The AMD card performed worse than my old 1080ti on that specific game, which I later found out because AMD had (maybe still does) huge performance issues with the CryEngine.
After a month of messing about trying to get it to play well I ended up returning the card for a 3070ti instead and just never picked up the game again.