Which they won't, because it's Apple
They made it clear they have no interest in supporting those GPUs anymore. They want everyone on the iGPUs of the M series chips. These GPUs are insane no doubt and are capable of great things, but for industry professionals it's not enough.
It seems from, at the very least, Apple's claims, that the M2 Ultra GPU will handily beat out any one single GPU option that was available on the 2019 Mac Pro. If you were someone who bought a 2019 Mac Pro and only had one GPU (with no interest in adding a second one to the existing one), it sounds like what you'd get with any M2 Ultra configuration would be an upgrade in performance. So, other than industry professionals that specifically needed either (a) 2 of any one MPX module or (b) any of the Duo MPX modules, I'm not sure how you can make that claim.
Again, as a disclaimer (since this is clearly a hot button issue): I'm not saying the 2023 Mac Pro is a viable replacement for ALL 2019 Mac Pro customers. Clearly those who need more than 192GB of RAM are screwed. But, Apple, having just spent the last decade under fire by Pros for producing insufficient workstation options, likely calculated that this Mac Pro, while alienating some, wouldn't alienate enough for it to be a repeat of the trash can fiasco.
