I’ve been called worse 
What I suspect might have happened is that following a series of complaints to the DWG, I reverted a large number of mechanical edits yesterday. The mapper concerned didn’t appreciate this, and sent various messages to me immediately after that block and revert. The “new account” performing this vandalism then appeared immediately afterwards. This may of course be a coincidence, but it’s not the first time that this particular scenario has played out with this individual.
The bad news is that they’ll probably try again with another “new account” from another throwaway provider. The good news is that, as here, it’ll all get reverted pretty quickly, and limits on the creation of “new accounts” and what new accounts can do is more limited than previously to prevent damage.
Edit: Actually there are at least 3 accounts (blocked); as noted above I’m sure we’ll see more.