He said AMD Ryzen which works great with open source drivers that are part of the kernel. I've got a Ryzen 2 laptop and everything works perfectly under Ubuntu out of the box.
PopOS supports nvidia, intel and amd graphics pretty well out of the box (nvidia was a separate download, unsure if it still is).
I had trouble with the 5700 XT for the first few months though... Other than running out and buying a new graphics card series when it comes out, most people should be fine.