alt Hacker NewsDX11 is much more high level while DX12 implements direct control over the GPU. 12 is much more like vulkan.
I guess since this is emulating the device instead of just passing the commands to vulkan it is easier to do DX11, but I could be wrong about this particular implementation.
DirectX 12 isn't just much more like Vulkan, it's so shockingly similar, it's basically Vulkan. It's jarring when you read it for the first time because you ask yourself why it even exists, but a second later, you realize it's so Microsoft can own their own graphics interface, too.
I could be remembering this incorrectly, but that's the impression I remember.