That's weird. I've only had two or three old, presumably unmaintained Linux ports not launch on my PC. I use AMD hardware. It appears for native Linux ports that they need to be maintained more to continue fully functioning over many years. In that regard, Wine/Proton can be much better for old games then native, but I've only had that with a few games as I mentioned, all of which were 10-15yr old ports.

Many games with native Linux support don't work very well even when they superficially seem to.
I play 7 days to die, and the gas flames graphic doesn't work so they are completely invisible, so you walk right into them and die.
The Proton version however, everything works.
Same with divinity original sin enhanced edition, in the linux version left alt button doesn't work to show items that can be picked up, and it can't be remapped?
Again in Proton everything works perfectly fine.

I think all in all, it's more than 50% of games with linux support that work better with Proton!?