These users will either have to give up user-serviceability and buy a Mac Mini or iMac, somehow pony up more money to get a $6000 Mac Pro, or abandon macOS unless they go the Hackintosh route, which is not an option in corporate environments and other places where EULAs are enforced. This is the choice that Apple presented us with.
The (non-Pro) iMac is a great substitute if they don't want user serviceability.
I personally don’t even care if it’s AMD instead of Nvidia, I just want stronger card options. The fact that the GPU in the top config iMac Pro is just on par with my now-old 980Ti really sours it.
Note that I’m saying this as a long time Mac user and iOS dev using a hackintosh tower alongside a couple of MacBooks.