I stopped dual-booting 5 years ago and I already was able to play most of my library back then. It gets better every day and I even almost forgot about adding launch options now, as they mostly run out of the box.

Anti-cheats might be a problem, especially the devs of the game refuse to use its Linux version. Or the anti-cheat is kernel-level. I also run into some games that use weird custom-made engines that won’t run. They were niche Japanese games, so I kinda understand.