I find it hard to believe Apple would limit the growth of their top end machine. The very reason I have a Mac Pro is the advantage I can take of new technologies to handle ever increasing software workloads and data handling. I could not justify buying the 2023 Mac Pro(not a money issue) and the GPU is a most critical piece. I totally support engineering changes to the Mac Pro to permit GPU enhancements.
I am hoping there is a better Mac Pro in the works so I can buy one and stay with Apple. I've done Linux before and can do it again, especially if others produce ARM chips for expandable systems.