This comment seems a bit strange to me for a few reasons. The Linux ecosystem has changed and improved drastically in the last few years, and a lot of this reads like it was written a decade ago.

AMD drivers have been rock steady for quite a few years now. The catch is that unless you're doing some exotic thing (not general-purpose gaming) you should not be installing anything extra. People used to downloading drivers for everything tend to make the mistake of hunting down and downloading the Radeon proprietary drivers when those are not needed, and in some cases actively make things worse. I suspect this is the case because you mentioned Mesa when talking about the integrated graphics card, but not the dedicated one. If I'm right about that, uninstall Radeon and let Mesa handle it with the AMDGPU open source drivers built into your kernel.

Unfortunately, dual GPU setups are still very painful and annoying to set up and use. That is still an active pain point in the ecosystem. DRI_PRIME is still the best solution for this afaik, but it isn't exactly an elegant one.

Steam comes with Proton built in (their own fork of WINE with a lot of improvements), WINE & Proton have made gigantic leaps forward with the backing of Valve, and pretty much everything gaming related has moved from OpenGL to Vulkan. Anything run in Proton, for example, is going to be using Vulkan, not OpenGL

Checking out Metro's protondb page, yeah, seems like the consensus is that the devs did a shit job with their port. I'd recommend right-clicking the game in Steam, go to properties, compatibility, and enable Proton there.