These APIs are just to control the GPU, they are just complicated to give developers flexibility. Just because you can't think of uses for these features for gameplay doesn't mean they don't exist.
Perhaps I'm misunderstanding "The fragmentation is a sign of desperation" but Metal, Vulkan and DX12 have very clear reasons they exist:
-Metal was created by Apple to unlock features that their GPUs had that OpenGL ES 3.0 does not support. This is pre Vulkan so that wasn't an option.
-Vulkan addresses the desire by developers to make more low level use of GPUs. AMD Mantle started the trend but it became clear that either a standard needed to be developed or every platform/gpu maker would have their own API.
-DX12 was created as the successor to DX11 to address the same issues as Vulkan but in the way that the Microsoft team wanted to.