> Proton represents Valve's failure to make Linux gaming attractive to game studios.

> Not even those that have Android/Linux NDK builds, bother with porting to GNU/Linux.

It is a huge hassle to make a new build to a new platform. You double build system, release management, and testing. Compared to just one plat. Games are complicated, and testing all the dynamic behaviour is also complicated.

Making just a Win32 build really saves resources.

Also Win32 has been a stable api for a long time. Linux apis tend to change, and old games don't get re-built. The win32 build is therefore also provably a lot more long lived, compered to anything you build on linux.

Thats also important because of the Dont Kill Games effort and so on.

That reasoning fails flat given the same studios have no issues supporting iOS, PlayStation, Swift and XBox, which are completely alien to what is used on Android NDK, APIs that are GNU/Linux compatible for 3D rendering, audio and asset loading.

Valve basically failed to provide the business value for those studios.

Microsoft releases new APIs too, but no one uses them, especially not games.