It's very low level. Khronos noted, that they didn't have time / resources to create a higher level API (on top of Vulkan) that would at least match the level of OpenGL in usability (but would avoid its downsides like stateful nature). Hopefully someone will make such higher level library. Engines can't fill that role - they are too high level and specialized already. So that middle layer is still missing.
Because OpenGL is stateful by design. Since there isn't anything else high level enough, OpenGL is still useful, but yes, I expect it to remain only for legacy applications once something better based on Vulkan will emerge.
