The truth is that Intel spent a lot of time plugging away at all the different mechanisms that you could try to get performance, and one of those is high bandwidth peripheral interfaces. Apple hasn't got there yet, it doesn't have a chip with a tonne of transceivers on it that it can use to hook up a massive GPU, and to get there they need to not only get all the transceiver work sorted, they also need to build an entire software stack to deliver that performance. All to benefit the lowest revenue product in their line up chasing a sector that's not growing.
So what will happen? The same thing that happened with all of Apple's bad products- they'll continue to offer it for sale at incredibly high margins for eternity and never attempt to make it more competitive. Let me point you to the Mac Pro Trash can, it was almost immediately obvious that the product didn't deliver. What is the reasonable thing to do? Do a redesign as soon as possible! What did they do? Quote from Wikipedia:
>On September 18, 2018, the Mac Pro surpassed the Macintosh Plus's production life record for an unchanged Mac model, with the Plus having remained on sale unchanged for 1,734 days. It was discontinued on December 10, 2019, after being on sale unchanged for a record 2,182 days.
The new Mac Pro is going to be here for a very long time is my guess.