This might make a bit more sense now. It appears, by your typed comment in the Message field, that you CAN edit it. And your question is only “why does it say ‘only moderators…’” and why is this selection ‘greyed out.’
Changing the permission is a ‘behind the scenes’, in Preferences/Settings thing – not right ‘out front’ on the page being edited.
Have you been back to the Settings page for the Wiki’s? And this one in particular?
Dan Tucker, Groups.io AFDRetiree’s Group Founder/Owner/Moderator
From: "firstname.lastname@example.org" <email@example.com> on behalf of Bruce Bowman <bruce.bowman@...>
For some reason I can no longer change edit permissions for wiki pages on a page-by-page basis. See screenshot.