That's ostensibly why the system is good for lawyers and law enforcement. It seems like it's only bad for domain owners. And I really question how useful it is

That's ostensibly why the system is good for lawyers and law enforcement. It seems like it's only bad for domain owners. And I really question how useful it is for even the purpose you outlined. Considering that a) your registrar could easily be subpoenaed for this information if there's a genuine need and b) Anyone who has the tech savvy to register a domain with plans to do something illegal with it surely also realizes they can register a free email under a bogus name.