Perhaps so, but they haven't seen a design win for a discrete GPU on the Mac since 2013 for the iMac, and 2014 for the Macbook Pro.
That happens to be not terribly long after Apple started offering rewrites of their pro apps that went all in on OpenCL.
Nvidia did put out a driver for the cheese grater Mac pro so it can use Pascal based cards, which is nice, but I imagine that's motivated by a desire to maintain CUDA dominance.
And yet: https://www.phoronix.com/scan.php?page=news_item&px=GTX-1080...
OpenCL performs great on Nvidia.