I would say anything multiplayer that dumps you into a cruel world of 10-year veterans of incomparable skill and/or wealth. Persistent survival especially for avoiding matchmaking in favor of unfair encounters.

Eve - huge space game has a reputation. Something something nullsec, space pirates. Foxhole - you're a grunt in a huge war machine. Good luck surviving the grenade spam, artillery, tanks, machine guns, and that bayonet guy who can dodge bullets. Rust (also Tarkov, DayZ, etc) - you're too poor to afford decent guns and armor, but you have to risk it anyway to stand a chance in the PvP hellhole of players who shoot on sight. They're better shots than you. They see you first. And they brought more friends. Ark: Survival Evolved - try the persistent official servers, face Kaiju ultra-dinosaurs that have been bred to perfection since launch. Try PvP clusters, and clans speed run to the cheesiest endgame content then wipe your base on day 2. I'm a gaming masochist and this game was too much for me.

The weird thing is that there are hero players. The ones who win 1v3s without a sweat. They're just not you. You're fighting them. You won't be them until you've dedicated 2000 hours to git gud.