From what I hear its because he sent someones Ip to them-self. Its like going up to someone called "Mr Autismo" and saying hey I know your called Mr Autismo.
Imo the situation escalated when the report on onion showed the thing Onion apparently leaked lol.
So if I dox someone and get their ip, address, full name and tell the person who I doxed there's nothing wrong with that?