Board Thread:General Discussion/@comment-31924693-20140509094043/@comment-452-20140509152700

By the way, you might be interested in this discussion from October 2012: Forum:Why is a user able to edit someone else userpage %3F

As I mentioned back then, there is an extension for this: Extension:UserPageEditProtection, but Wikia Staff refuse to enable it.

Also as I mentioned then: Blog posts are locked to the owner, therefore User pages should be too.