A project I've been working on for 2 years is now out in the wild (Proton bleeding-edge branch, enabled by default for 4 games: the non-special-edition Skyrim release, Mugster, Clustertruck, and Red Faction). It add gamepad support to launchers that don't have it built in. https://github.com/ValveSoftware/Proton/commit/627d220fa3d7a489ddf258a96b2bf557604d5db9
This is real and not an April Fools joke.