MoltenVK original intent was to let developers work on a mac system developing
for the vulkan eco-system. MoltenVK doesn't support all the features that we
require and would require additional workarounds to be actually supported.
It is not expected that we will release Blender with MoltenVK for this reason.
But it still has value for shader developers to validate shaders on metal and
vulkan on a single platform.
Pull Request: https://projects.blender.org/blender/blender/pulls/117940
c15e5116ab