Windows drivers contain game-specific optimizations (low level tweaks and rewrite shaders that will be injected into app) to make them run faster. I can't imagine Apple doing it. Of course, the hope is that modern APIs make these kind of hacks unnecessary, that's also why Metal is so much closer to DX/Vulkan than OpenGL was.
Agreed, apple won't do it. But still. Given the macOS drivers aren't 1 gig in size and full of game-specific performance hackery, running GAMES within 50% of a top flight game optimised PC GPU in less power is impressive - and people poo-pooing that level of performance need a reality check.