Asking to see if there's been any definitive answer re this. Apple made a lot out of it being future-proof at the same time they were developing silicon in secret. To me, this should mean they knew it could be upgraded at some point.
Mac Pro, macOS 10.15
There has NEVER been any official indication from Apple that your Hardware will be provided with a drop-in upgrade, at all, ever. Any assertion that Apple has made such promises are simply not accurate.
What Apple has done, and done extremely well, is to make certain that all but the most wonky Applications are all working on newer Macs directly, with newer MacOS and completely different processors. No modifications are required to get them running, and developers were provided with straightforward pathways to re-compile for the new processors, should they decide to do so.
Executive Summary:
There IS a trouble-free pathway to the future.
It does NOT include a drop-in upgrade for your current hardware. But your current Hardware continues to be supported.
Upgrade 2019 Intel Mac Pro to Silicon
