I got a Radeon 7800XT in March and have had no significant issues with it on Arch Linux. The issues I have had were from running the bleeding-edge mesa-tkg-git drivers which are the pre-release development builds, and sometimes things break there (I had a weird issue where red and green got swapped in X11 apps). You have to go out of your way to run those drivers though, stick with the released version in your distro’s repository and you’ll be fine. I can play most games above 100Hz at decent resolution and quality. I have a 4K 144Hz monitor with Freesync but for more demanding games usually need to turn down settings a bit or use resolution upscaling like FSR. I upgraded from an Intel Arc A770 and it was a big performance increase.