I had a situation like that with an undocumented behavior and systemd-tmpfiles. I wanted it to clean up a directory in /var/tmp/ occasionally. The automation using that directory kept breaking, however, because instead of either finding a whole intact git repo to update or a deleted repo, it instead found only a scattering of files that were root-owned with read-only permissions. There was yet another undocumented feature in systemd-tmpfiles where it would ignore root-owned, read-only files regardless of explicit configuration telling it to clean up the contents of those directories. Eventually this feature was quietly removed:

https://bugzilla.redhat.com/show_bug.cgi?id=1780979

https://github.com/systemd/systemd/commit/a083b4875e8dec5ce5...

That was far from the only time that the systemd developers decided to just break norms or do weird things because they felt like it, and then poorly communicate that change. Change itself is fine, it's how we progress. But part of that arrogance that you mentioned was always framing people who didn't like capricious or poorly communicated changes as being against progress, and that's always been the most annoying part of the whole thing.