Proton with what? Stable or experimental? DXVK or Wine3D? X11 or Wayland? Nvidia closed source or open source?
That's just what I came up with. There are probably a few more of these questions. Even Proton alone is not an easy target.
Especially if you want some low-level anticheat. And you know, if they have one platform that is easier to cheat, cheaters will all use that platform.
I don't know about you, but playing with tons of cheaters doesn't seem like a lot of fun to me.