That's literally why I'm a member of a Trade Union - so that I have legal representation check my employment contracts before signing them. And why I have a lawyer check the paperwork when I buy a house.
These services should publicise their name dispute policies more openly. But, ultimately, they can enforce their private property rights on the usernames they control.
You should perhaps teach a class in responsibility deflection. It's very impressive how you are able to do something that, while perhaps inline with T&C, is indisputably a dick move - and turn around and blame everyone else! Just own up to it dude. The companies have bad policies, and you were a bit of a dick, them's the breaks.
These services should publicise their name dispute policies more openly. But, ultimately, they can enforce their private property rights on the usernames they control.