I had the same problem and tried a bunch of stuff (mediawiki, confluence, GitHub wiki, gitlab wiki, shared drive, Wordpress, SharePoint) and currently just use GitLab pages because the fork/merge flow for markdown was easier than trying to grant access and moderate a wiki.
It’s still easy to solicit edits, but the issue/question flow is helpful, and have some review process seems to help. Lots of people struggle with git mental models, even using the built in browser IDE in GitLab and GitHub. But most engineers seem to be able to handle.
Conjecture: almost every belief that your wiki needs support for ACLs and needs to be moderated (for any reason other than spam) is a belief that's wrong from the start. (And it should be a criminal offense the way that GitHub and GitLab to have corrupted the word "wiki" to be understood to include PR- and review-based workflows centered around big collections of offline source files—the very practice that the wiki was created in reaction to, as a means to solve the problems inherent to that workflow.)
It’s still easy to solicit edits, but the issue/question flow is helpful, and have some review process seems to help. Lots of people struggle with git mental models, even using the built in browser IDE in GitLab and GitHub. But most engineers seem to be able to handle.