Jason Snell, writing at Macworld:
So what makes a Mac Pro a Mac Pro? If it’s a tower enclosure, Apple’s got a relatively fresh one from 2019 that it can just roll out again. (Gurman says that’s now the plan, which is also a little disconcerting when you consider that the original reports suggested a new, half-height enclosure and that quad-M2 chip.) But what’s inside the Mac Pro matters, and if it’s just an M2 Ultra chip, it’s hard not to consider the new Mac Pro just a Mac Studio that moved out of its apartment and into a mini-mansion.
Does it help if there’s expandable internal storage? Sure, I suppose–it’s certainly a lot neater than attaching drives via external ports. Does it help if Apple offers additional M2 GPU cores via some sort of proprietary add-on card system? Maybe, if it’s done the extra engineering work. What about RAM expansion? Sure, but again, such a choice would undercut the work Apple has done to create a pool of fast, shared memory right next to the CPUs and GPUs.
And all that custom work, all those distortions to what makes Apple silicon so successful, would be done for a product that’s a niche of a niche–and it’s work that Apple’s chip design team could have spent on a next-generation chip for the iPhone, iPad, and Mac.