It’s not Twitter’s fault
In 2014 Facebook estimated that between 5.5% and 11.2% of the accounts are fake. Real name policy or no real name policy. Twitter does not exactly have a bogus-name-if-you-wish policy either. The signup form asks for “full name” or “first and last name” in some other languages, just like Facebook.
Policy-abiding users will not abuse the system regardless of the name they provide. And you would really need to check passports or credit cards to enforce anything on trolls (will not happen). The key here is not policies, but the nature of the medium.
Facebook is a “share stuff with your friends” type of site. In tune with that, the issues and scandals around Facebook typically have to do with privacy. Twitter was developed and positioned as an open public venue for free speech and discussion. Would could possibly go wrong there? Exactly.
While Facebook’s privacy injuries were mostly self-inflicted, Twitter is battling a force of nature. Dealing with an issue like that is a very difficult task on many levels, not just technical. Still, many are bound to have the perception that, in fact, it is not all that complicated, just do X or Y (do it already! why aren’t you doing it??). Twitter will continue to allow pseudonymous (anonymous = ‘no name’, I am a nitpicker) profiles. They know that outlawing them will not do any good.