Complete speculation but could be that Apple supports these operators on their GPUs and they need end-user models optimized to use them. Apple makes their money on consumer devices and need them to be performant for inference on the edge. Getting NVIDIA to integrate the operators may result in more models optimized for operators Apple's devices can leverage to stay ahead of other edge GPUs.
Apple inference is on their own GPU. Apple training is on the cloud with Nvidia.
There are plenty of use cases e.g. Apple Maps, News etc which are public and don’t need their Private Compute Cloud.