Isn't the de-facto answer to this 'Unity' or 'Unreal Engine' ?
HN folk doesn't like to hear it, but that is how the game industry has worked since the early 80's where each gaming platform was a special snowflake.
There is a thriving industry of game engines and middleware that grew from there and the majority of game studios doesn't spend more than the time required to select which middleware they want to use.
Even for those that build their own engines, the graphics abstraction layer is a tiny portion of the engine, versus everything else that isn't covered by Khronos standards. Meaning GUI support, font, texture and shaders loading, mesh rendering, scene descriptions, game editors,....
Usually adding a new rendering backend to an engine doesn't take more than around one month, the biggest time slice being consumed by time to first triangle.
Given that Vulkan specification already has 74 extensions and is only at version 1.0.42, already bringing up the fun of "write once, port multiple times" from OpenGL, I am not confident this is going anywhere.
https://www.khronos.org/registry/vulkan/specs/1.0-extensions...