Many of us who were involved in the creation or maintenance of the original math pages agreed on Facebook recently that some of these pages should be protected. We are talking about the hardcore math ones that most users don't understand anyway, and shouldn't be playing with unless they get the material and are on the same wavelength as the people who originally created those pages. This is because as several of the original authors have sadly passed away (notably Gene Ward Smith) and the rest of us have been too busy to monitor for changes recently.
However, there are some Discord folks who are mathematically inclined and have also been doing very good work, so if there is some page where users like e.g. Inthar have added a bunch of original material then we left it unprotected. We mostly tried to focus on those pages which they aren't involved in and which have been rarely edited since they were added (like Don Page comma). Most of the edits to the protected pages were only done by me, XenWolf or FloraC and these users should still be able to edit these pages. There are also many pages which were initially from the math people, but have since become larger community pages and we also left them alone.
If I accidentally protected some page that people were in the middle of working on, leave me a note and I will unprotect it.
Beyond that, going forward, if you have any big project or initiative for the math pages, or suggested changes, please kindly use the talk pages to summarize your suggestion, or make a temp page in your userspace with the changes, and if it all makes sense we'll merge it in.