Its a combination of Vulkan and Valve paying devs to work on Proton.
Vulkan is a fantastic Graphics API. Vulkan is more optimized than DirectX, and it’s so much better than DirectX that the DXVK (DirectX to Vulkan) Wrapper that Proton implements makes games run better, despite the fact it’s running through an obfuscation.
sorghum@sh.itjust.works 11 months ago
I believe the biggest factor is Linux’s better resource management.