To clarify there are several very popular online games with anti-cheat that will never work BUT there are also a ton of other multiplayer games that do work great. You aren’t going to be stuck in single-player only moving to Linux, you’ll just miss out on a handful of popular competitive games.

Ocenaudio for audio editing. It’s not FOSS but it’s native, simple to use, and doesn’t have backend library issues I kept having with audacity.

I’m not a musician but I recently stumbled across https://linuxmusicians.com/ which seems like a decent forum for people that are determined to make it work.

Have you tried Deadlock? Coming from Dota2 I found it pretty easy to get into even though it is FPS.

If it’s just a matter of pulse selecting the wrong device I also had that issue and was able to work around it by adding a line to the end of my: /etc/pulse/default.pa
set-card-profile alsa_card.pci-0000_0e_00.3 output:analog-stereo+input:analog-stereo
You can get the correct name for your device with: pacmd list-sinks