My brother wanted to play CoD Warzone with me and of course it doesn't work with Proton. After attempting and failing to dual boot into Windows (how hard could it be to create a bootable Windows installation usb key?), yesterday I decided to try vfio. It actually was quite straightforward and way simpler than one would expect from the very intimidating archlinux wiki page. I spent more time getting a nice grub vfio menu entry than actually setting up the VM.

Of course now I expect I'll be eventually banned for running under a VM.

Proton support for anti-cheats can't come soon enough.