Orphaned Tag Wikis are sad. They hang around, shambling, and groaning and wait... that's zombies. Or maybe teenagers.
What does happen in many cases is they can be ambiguous, get misused, and on some larger sites end up needing many man hours of cleanup.
On the other hand, people who create a tag ought to know what it's for. We can change them later. If its a new user, it also ensures the user's put some thought into it, and lets people review it better. Making them write at least an excerpt, that's peer reviewed. In short, can we make sure that the need and goal of any new tag is clearly stated when its created?