> There is all this talk that Proton will make people want to develop native Linux ports but I don't see any data or logic to back that up.
I haven't heard of this, honestly. I'd fully expect it to damper Linux port development, and I'm not sure that's a bad thing.
It's entirely possible for a game developer to treat bug reports from Proton users as legitimate, just as much as they may for a native Linux port. Wine is effectively just another Win32 runtime that happens to run on the Linux kernel instead of WinNT.
I've had instances where the native Linux port of a game failed to launch entirely, but the Windows version through Proton worked flawlessly. I've also heard that some games perform better on Proton than native, because of the DirectX -> Vulkan translator outperforming straight OpenGL on Mesa.
Other commenters have mentioned this, but it boils down to market share. Linux's market share is downright trivial. If I was a game dev being raked over the coals for a release date, I wouldn't frankly give a damn over Linux, and I say this as someone who mainly uses Linux.
That's why I don't think this is a problem. If Proton becomes big enough then it becomes another "target", just another runtime to replace the old glibc/mesa one that devs can test if they want to.