On the question of how well Proton works vs. native, the thing about some of your points is that people expect Proton not to work. I mean, yeah, they figure it will work most of the time, but failure is part of the normal parameters of using a thing like Proton; if it works that's a positive. Whereas people expect native to work, reasonably enough, and if it doesn't that's a negative.

Nobody reports it to the devs when they try a Windows game in Proton and it doesn't work; they know it's not supported. And nobody is going to buy a game with a native version, start with Proton instead, find it doesn't work, and then complain on a forum that Proton didn't work, only to have the native version recommended. It's not a symmetrical thing when it comes to how and whether people complain, so I think it's plausible you could see more complaints about native even if Proton doesn't on average work as well.