Didn't Unity and Epic have people working directly on the Vulkan specification? I remember reading a comment (maybe here!), way back during Vulkan's original release, where someone was screaming about how Vulkan was a conspiracy to make us dependent on giant, multi million dollar game engines.
I don't know about any conspiring, but I've thought about that comment often, because the result appears the same: The barrier to in-house game engine development has been risen further.
I know Unity does, I forget if Epic does but I'd be surprised if they didn't.
Not really a conspiracy so much as the fact that Unity/Epic have much more opinions on what a graphics library can/should be than a small engine developer. The former don't care if it takes longer to release games, they have staff around the clock working on the engine.
I don't know about any conspiring, but I've thought about that comment often, because the result appears the same: The barrier to in-house game engine development has been risen further.