Usually boils down to a given category and combination of main elements. Open world, survival, crafting, automation, FPS, rogue lite/like, RPG, inventory management, RTS, puzzle, first/third person, action combat, tat target, top down, isometric, etc.

Of course, there are heavy outliers, but those usually require heavy wiki / youtube use to even get into. Same with spreadsheet simulator games where mastery does not necessarily come with time but understanding of hidden mexhanics and synergies.

As an example, I used to play WoW a lot and raided a lot, then got back into GW2 after 10 years (where I didn't do any dungeons or big raids, and if I did I couldn't remember), and didn't have problems with mechanics as others who were playing for several years. The mechanics just make sense, even when it is a new one - stay out of red circles, stack during attacks that split damage, damage phases etc.

When I got into Valheim, I already knew what would be needed without having to see any tutorials - build a house, make a farm, roughly where to look for what, and how to find info correctly.

There is not much I havent explored in my younger days, and throwing me into an FPS game I haven't played would probably mean I'd be in the top quarter on my team in two or three games.

When started Helldivers 2, I could no problem take on diff 8 (out of likr 10 or 11) and stay up to speed with others way before I unlocked it, as lower difficulties did not pose much of a challenge besides not having the top gear unlocked.

Sure, I won't know immediately what to do or how to control the character, but when I see a streamer struggling to clear content and see they throw points into defense on an attack character especially when it HIGHLIGHTS the recommended stats (looking at Clair Obscur), I just wanna tip my eyeballs out.

I am usually having a hard time with choices regarding optimization, like when I get to choose "do you want 1 level up or 10 attack power", bitch I dunno. But we are back at spreadsheets.