Yes, unfortunately it is. Contrary to what some may claim, supporting two UIs has both an up-front cost as well as a maintenance cost. Part of IP2’s motivation to get everyone on one code base was so they could get to a point where they could implement each new feature only once. I can’t imagine they’d want to go back to the old model.
At this point, useful feedback involves correcting the course for the new UI. It’s not helpful to keep repeating, “Revert!” If they’d wanted to have that option, they would have solicited feedback before the release.