If people make a big enough stink, we can change their minds. The 2019 happened because people complained.
Yeah good luck pal. Mac Pro users are a niche at this point, and a market Apple's made clear they have no interest in supporting much anymore since it's not as profitable. They were working on an M2 Extreme chip for the Mac Pro but scrapped it when they realized said chip was hardly gonna sell, so why waste the R&D on a SoC that few people are gonna buy? Graphics professionals who would need those GPUs have long moved on to Nvidia workstations, so they ain't around to make a stink anymore. Not to mention, they're selling boatloads of Mac Studios daily, and the Studio is making them a lot more money than the Mac Pro did.
For each person who complains about the Mac Pro, they sell 10 Mac Studios to make up for it. So I'm sorry to say man, but upgradable Mac Pros are on their way out. Even the usecase of putting BlackMagic cards into PCIE is on it's way out as there's new rack mounted BlackMagic solutions that perform better than the PCIE ones did.
Honestly it feels like this may be the last Mac Pro as we know it, and by M3 they're gonna push everyone to the Studio