I think OpenCL was a pivotal moment. Apple created the draft and donated it to Khronos, where is subsequently was stagnating before Nvidia effectively sabotaged the effort in order to push its own proprietary CUDA. Since then Apple has been focusing on their own hardware and ecosystem needs. I think the advantage if this is well illustrated by Metal which grew from being this awkward limited DX9 copy to a fully featured and very flexible yet still consistent and compact GPU API. Sometimes it pays not having to cater to minimal common denominator.

In the recent years I am more and more convinced that open standards are not a panacea. It depends on the domain. For cutting edge specialized compute open standards may even be detrimental. I’d rather have vendor-specific low-level libraries that fully expose the hardware capabilities, with open standard APIs implemented on top of them.