Apple has their “Afterburner” card for ProRes media encoding, you could add even more ports, or there’s probably weird AV interface cards, but the vast majority of people can save a few thousand dollars and get a Mac Studio instead.
Since the Mac Studio has more than 10 customers it gets updated more frequently.
There were rumors about the Mac Pro getting a higher tier of “we stuck twice as many cores together in the SoC” but it didn’t pan out, likely not worth the development time compared to the higher volume products. But it could hypothetically still happen.
therefore I expect that mac pro (and in similar vein mac studio) will be repositioned as ai/ml dev machine, with apple leaning into their lucky strike of UMA fit with modern requirements.
my bet is m5 extreme exclusive to mac pro and 1 tb possibly even 2 tb ram, and mac studio limited to m5 ultra and 1 tb ram on the high ends.
but thats not based on rumors or "news" of any sort, just from logic extrapolated if i were in apple shoes