Intel or AMD is gonna build a CPU that breaks Linux.

Those are the last manufacturers you could expect to see pulling something like that, it won't happen because the majority of servers run Linux, same on several enterprises' workstations. To support that even more, the drivers by both are open source offering better/easier integration with the kernel.

I believe your playback issues could be related to missing codecs, ffmpeg on its own shouldn't be what enables that as far as I know, perhaps in the past it pulled in a certain codec as a dependency so as a side effect videos started playing.
Those other input related things could have been using X instead of Wayland or applications running in compatibility mode (XWayland).

If you feel like giving it a try again I think you would be really happy with Nobara Linux, it's perfect for a fully fledged installation that doesn't need you to do much or any further tweaking, it's also generally better for gaming, not sure if it will solve all your issues on that front, but do try to run those games through Steam or Heroic, or the more generic Lutris or Bottles