Wasn’t there evidence that anonymity doesn’t actually play as big a part as people keep saying? Most of the Twitter abuse, you can generally identify who it is behind the account, it’s more the forum than the anonymity?
The medium is the message. One of the messages of the Internet, as a medium, is abuse.
Now, whether the take-away is "we should try to regulate it to stop that", or "people should stop using it to post details and thoughts, alongside PII and all tied to one traceable identity, that they wouldn't ever post to the public-use notice board at the local grocery store, because it's fucking insane (as Zuck might put it, they're 'dumb fucks') to post like that on the Internet and expect it to go well", or something else, is a matter for consideration.