> In short I guess if I disagree with a page instead of editing it and starting an edit-war I can fork it.

Which I'd expect to lead to less of a "chorus" and more of a cacophony of voices as every disputed change, every contentious rewrite, leads to another fork of the original.

Merging software branches can be hard enough. Merging "forks" of English text is horrendous, and gets worse the further the forks are from each other. There's a good reason why no commonly used wiki software has this functionality: it's completely impractical to use.