If Apple cannot do their own implementation of CUDA due to copyright second best is this; getting developers to build for LMX (which is on their laptops) and still get NVIDIA hardware support.
I thought that the US Supreme Court decision in Google v. Oracle and the Java reimplementation provided enough case precedent to allow companies to re-implement something like CUDA APIs?
CUDA is a set of four compilers, namely C, C++, Fortran and Python JIT DSLs, a bytecode and two compiler backend libraries, a set of compute libraries collection for the languages listed above, plugins for Eclipse and Visual Studio, a GPU graphical debugger and profiler.
Apple should do a similar thing for AMD.