The versioning makes sense -- but it seems like it could get unwieldy pretty quickly. (I'm thinking of the technical documentation site I actually work on, with thousands of pages, several of which get minor-to-significant updates on a weekly basis!) It also sounds like a design particularly ill-suited to, say, a news site with a front page that changes several times a day -- or, for that matter, a site like Hacker News -- although I suppose the notion of one-way "jump links" might have been the intended answer?
And, yes, the mandatory identity for all users sounds like a potential privacy nightmare.
It would have been different, no doubt about that. However, it's not like we don't already version everything internally. Wikis keep every edit in the revision history, we put all our code in git, etc. Even back in the day VMS systems had a version number as part of every file name, with the OS automatically keeping past versions of every file. It's just that there's no version field in our standard url syntax, so there's no standardized way of using retrieving those versioned documents.
And, yes, the mandatory identity for all users sounds like a potential privacy nightmare.