So, why not fork wikipedia? What's to stop that? Or is it like, it's not ideal, but it mostly works ok?
On the whole, my own experiences with Wikipedia have been more or less ok:
- as a contributor: on high traffic pages, trying to edit something is not going to get very far. But... whatever
- as a contributor: on low-traffic pages, as far as I know, edits mostly go through, unless you say something that conflicts too much with someone else's agenda. Adding equations: works ok. Adding some opinion on someone's personal bio page: might not get very far
- as a reader/end-user: most stuff is approximately correct, most of the time, at least for the uses I make of it, ie looking up some scientific or mathematical concept