It's not a workstation anyway. Workstations these days can have four Nvidia A6000 cards and dual Xeons and massive amounts of RAM (terabytes).
Now it's just a Mac Studio in a fancy looking bigger box with no ability to add more RAM beyond what it was ordered with.
It used to be a workstation when up to 1.5TB RAM (even 2.0TB) and dual W6800X Duos could be added in the previous times (August 03, 2021 the W6800X Duo was released). If you don't care for MacOS then you can quite freely add 4090s or even W7900 Radeon Pro cards and run them in Windows 11 Pro for Workstations.
Apple must make support for Mac Pro 7,1 as restricted as possible. They have to ensure external addon cards don't work properly and severely restrict GPU addon options to force those despicable 7,1 users over to Apple Silicon otherwise they'll just keep using the 7,1 for years and years. We can't have that, surely...
Because my 7,1 is working so well I ordered a second machine, also very high spec. I'll probably add more RAM to both of them soon, otherwise don't need to do anything else.