PlayStation doesn’t use DirectX or Vulkan, it has its own proprietary graphics API. So PC ports will still need completely different DirectX/Vulkan-based renderer. And given that API is different, its AMD driver certainly works differently from Windows driver too. I doubt that underlying hardware being similar will help much in this case.

There was no move in the first place. AMD took so long to open source AMDVLK that RADV was already in a usable state (and used by Linux distros) by then.