This has been a problem for a while now, but on the yuripedia wiki where I'm an admin on there's another admin who seems to insist on sysop protecting nearly every page on the wiki. I've tried to explain why this isn't allowed in the past, but it seems to do no good. The user is a good content creator and I'd like to avoid blocking them (or removing the sysop flag) if possible.
Feel free to use Special:Contact with this (as well as links to the wiki/user), and preferably also what you would like staff to do. It is likely that they will talk to them either way and unprotect most pages, but as you say, it's not allowed to protect the majority of pages on a wiki