> users are still served only by the proprietary driver [...] An open source Vulkan driver on Windows opens up a number of possibilities: a shared codebase across platforms, easier debugging and experimentation, faster turnaround on fixes, and a path for the community (e.g., game developers) to report problems or contribute improvements that benefit everyone regardless of operating system.

To me, the argument against a proprietary driver seems extremely weak if you're running Windows anyway, but I guess they see it more that if more game devs can run the RADV driver, they can get wider testing (or a simpler story for devs to test at least) and backdoor improvements into the Linux side?

I guess I dont understand the "a shared codebase across platforms, easier debugging and experimentation," comment. Shared RADV codebase? Or shared game engine code, at least the specific parts of the engine that target Vulkan x Radeon (how big is that really?). Similarly I guess "debugging" here is tracking down odd ball RADV bugs where you could then run it in windows to see if its a linux thing or a RADV thing?

Most of the PC gaming audience is on Windows, so Windows is still the primary target being developed against. Having better Vulkan on Windows means more support for Vulkan in games in the pipeline, which means better Linux support in those games over time, which ultimately benefits Steam and their hardware.