Macos is a real unix based OS. (As opposed to unix compatible GNU “Gnu is Not Unix”)
I've seen so many people say this over the years, and I'm still not sure why i should give a flying fuck. Additionally, when I worked on low level cross platform software, macos was the one that was missing posix functionally I had to replace by writing shims in objective c
If it handles proton or whatever it will be viable for less technically adept which is a good thing