Yes. Apple have their own graphics API. They were able to decide that, say, geometry shaders aren't worth the chip area or engineering effort to support. Other IHVs don't get that choice; for geometry shaders, for instance, they're part of both Vulkan and OpenGLES, there are games and benchmarks that use them, and customers (end-users, gamedevs, review/benchmark sites, SoC vendors) will evaluate GPUs based, in some small part, on how good their geometry shader support is. Same story for tessellation, transform feedback, and whatever else Apple dropped.