How long would it take you to establish enough credibility to be able to make an accusation like that and have people actually take your word for it? There might be a few nutters out there who are so predisposed to hate JFK that they'll believe anything negative about him, but most people - even those who dislike him - would rightfully question such an outlandish statement made by someone with no credentials.
Dishonest people retain credibility when their supporters are trapped in echo chambers designed to keep the truth out. Censorship is a powerful tool for establishing and maintaining echo chambers. We need to fight echo chambers, not promote censorship.