As much as I dislike Facebook. We have to stop to tell them they are responsible for anything. It's fully our fault whatever one can say is Facebooks. Everything else is just censorship and just as bad. There is no such thing as responsible censorship. One side will always get pissed and who are we or Facebook to decide what's right.
As an extreme example of good censorship look at child pornography. We have laws that prohibit speech in the form of harassment. Some countries prohibit anti-abortion protestors from harassing women trying to get an abortion. There are lots of cases where censorship is good.