Their justification for the form factor, when it was released, was that pro users need various PCI cards to interface with some of their equipment, and this would allow them to do that.

It seemed like the guts of the Mac Pro were essentially shoved inside of a box and stuck in the corner of the tower. It would seem like they could decouple it and sell a box that pro users could load cards into (like other companies do for eGPUs). It wouldn’t feel like a very Apple-like setup, but it would function and allow Apple to focus where they want to focus without simply leaving those users behind.

I suppose the other option would be to dispense with the smoke and mirrors and let people slot a Mac Studio right into the Mac Pro tower, so it could be upgraded independently of the tower.

The alternative is people leave the platform or end up with a bunch of Thunderbolt spaghetti. Neither of which seem ideal.