Note that Intel is only using a translation layer for DirectX 9, and from what I’ve heard online the result is bad performance. DirectX 11 and 12 are both implemented natively.
DirectX 11 and 12 are both much more aligned to the hardware. DX 12 took the basic principles from AMD's Mantle and is very similar to Vulkan and Apple's Metal. Therefore, it makes a lot of sense and is not too much additional work to implement these natively.
