The difference between censorship and moderation is the ability to realistically opt-out. Your friends might get mad at your for saying something, but you can choose your friends. Your community might not allow certain speech, but you generally get to choose the communities you are a part of. When the avenues where 99% of all communication go through "moderate" speech a certain way, that starts being censorship.
The difference is somewhat part who is doing the moderating, but it is far more important the ability to opt-out without significant negative impact.
The difference is somewhat part who is doing the moderating, but it is far more important the ability to opt-out without significant negative impact.