DX12/Vulkan is an equal failure. In virtually every multi-API game there's at least one instance where DX11/OpenGL runs better on at least one vendor. Also if you watch later patches in many of the games (e.g. Tomb Raider Rise) you'll see the low level APIs fail in ways no longer covered in mainstream reviews (e.g. crashing black screen, stuttering, etc).
It all depends on the quality of the implementation. Early DX11 titles often ran worse than DX9 as well, because developers had to learn to utilize the API properly. The same thing is happening with DX12/Vulkan, except the learning curve is much greater due to the APIs being much more complex and requiring a lot more manual input.
But when it's done properly, DX12/Vulkan blows DX11/OpenGL out of the water, no question about it. One of the best examples of that is with Doom. Both vendors got large increases in performance, due to OpenGL being fundamentally single threaded. Wolfenstein 2 builds upon that foundation even more, as the game outperforms Doom while having greater IQ and more graphical effects.