The problem with in-depth, detailed guides for MMOs is that they're outdated almost as soon as they're completed. Which is why community-driven efforts are the accepted norm: the community can react and change faster than a gigantic company where everything has to be run through legal, translation, marketing, etc. departments before it can be released. SE isn't going to want to commit all those resources to constantly updating detailed guides every time there's a patch that invalidates the information in the original.