Yeah, git is complicated and having a synchronized gitit across multiple servers would be kind of a pain to set up. Maybe someone could package that to make it easier. Or Lemmy could add a federated wiki just like Reddit has a wiki.
It occurs to me, you could also look at Fossil (fossil-scm.org). It is also mostly intended as a VCS, but it has a wiki built in, and it is quite easy to set up. Again though, idk about the setup for keeping multiple servers synchronized.