I'm not on Twitter for abuse. I don't think anyone's gotten on Twitter so that they can be abused, but people do go on Twitter to abuse people. When that becomes clear then Twitter has a moral duty to shut those people down when they see that somebody is there solely for the purpose of abusing others. Yeah you have free speech, but what you don't have is the right to wield your speech like a cudgel to somebody who has done nothing to earn it.