Seems like most mods work fine on Linux, but I'm sure it depends on the game. For games with built-in mod managers like Baldur's Gate 3, it all just works. For games with manual mods that involve replacing or editing game files, they should generally work since you're running the same game files to begin with.

I haven't had any big compatibility problems recently, though again, I'm sure it depends on that game. Proton (built into Steam) works very very well nowadays.

Just a few years ago I found the experience frustrating. It seemed like everything had something wrong with it, even if it wasn't big. Lots of games had glitchy input, whether using a controller or keyboard/mouse. But somewhere down the line it totally flipped, and everything I play runs great now. I still have a bootable Windows 10 system, but I haven't actually booted it in...two years, maybe?