Facebook didn't cause or perpetuate the situation in the USA, it simply reflects it, as any communications tool.
Let me tell you: Facebook sadly has no monopoly on partisan lies and associated screaming, or rampant misinformation.
I'm disappointed that TBL, who seems to be very smart, falls for it so easily. Like when he mentions "feminist bloggers" - these people get toxic replies because they write toxic articles and messages (basically "all men are assholes", so naturally some men get angry about the insult). Haven't experiments in fact found that men receive much more hate messages than women, they just don't make such a fuzz about it?
I don't think TBL actually advocates for censorship (except with his "curation" idea) when he asks for better controls. Good muting, blocking and reporting features go a long way towards making social networks usable.
Facebook offers shitty controls, and reads and influences our conversations. Unlike cellphone carriers.