Since February I've been running CachyOS or Fedora (multiple machines) 100% at home. I only have a Windows partition on the desktop for a single game.
Gaming "just works" on Linux with one AAA exception that needs a tweak to its Steam Proton settings. The UI to me is as polished and functional as MacOS and Windows - besides a few minor things like taskbar shadows or rounded edges, a non-techie wouldn't notice the difference IMO unless they already knew it.
I've been running Linux on and off for 20 years, and KDE 6 is the most happy I've been with a user interface, with Unity being second. Everything you can possibly tweak seems to be discoverable in the UI just like Windows or Mac.