Again, I think you’re coming at this from enjoying Proton today but say DX13 comes out tomorrow, it could be years before Proton is compatible.
It took about 6 years for Proton to be somewhat capable at supporting DX3D 12 after 12 launched in 2014. Arguably it was closer to 7 or 8 years (that’s how long Proton took to get to the state it’s in today).
This is what I’m talking about. If MS purposefully make it difficult to reverse and reimplement (which they have an incentive to do), and game developers continue to focus and target MS platforms, we could be waiting half a decade to play those games on Linux.