It would allow SSH if the desktop is locked, they’re separate. If you can get in via SSH then you can poke around logs like dmesg and see what’s up. There will probably be some messages to give you something more specific to search with.
Proton is amazing, but it’s entirely overhead translating library/system calls to Linux. It’s accurate to say they run better on SteamOS, not to say Proton is making it run better.
Now maybe Proton makes them run better than a janky but native Linux port, but that’s a separate statement about games being better optimized on Windows.
Intel has been struggling overall, and lately has been letting some of its Linux engineers go. Nothing absolutely fundamental has been affected yet (AFAICT) but I guess Clear Linux didn’t make the cut.