Yes, and the primary reason any of gaming on Linux is viable (steam deck, proton, etc) is due to Valve dumping money into it. AMD probably didn't care about the miniscule number of chips they sold to Valve for the deck, valve just wanted a vendor who had the performance, and had decent Linux support.

But Valve is the one eating all the vulkan costs that msft normally eats on the dx side. To be clear, it's never out of the kindness of their hearts, it's purely because a msft dominated gaming ecosystem on PC is steam's biggest weakness. They don't want steam on windows to reach the point of EGS on the apple store.