And yet, there are so many instances where their is no ambiguity about the lies. They are simply bald-faced lies, and there is no doubt that they are indeed lies. And Facebook is quite aware that they are lies. And those lies get very widespread distribution on their platform. And those lies have real political consequences.
In the land of the deceived, Facebook is king. (And those who are good at spreading lies on their platform.)
I suspect everyone can agree there are instances where there is no ambiguity about what is a lie and what is truth. But it seems unlikely that there is any consensus on which instances these are, or what the truth is. If there is consensus, then almost by definition censorship is not needed, because all the though leaders can identify the lie easily.
The argument in favour of moderation is to build a specific type of community, not to establish truth. The hope is that people will vote with their feet and move to communities that favour the truth.
People will move to communities that favor their truth, I suspect. Same reason they typically watch the news stations that reflect their biases.
It's convenient to make a statement into a boolean true|false. However, as we have learned many statements, especially in the political arena, are truths mixed with false premises, out-of-context quotes, partial quotes, and much more. Snopes and Politifact try to provide accurate in-between answers.. But yet, the damage was done.
And whom plays "truthmaker", Someguywhatever asked? Facebook? Google? Apple? Or the lord of some other fiefdom? Do we trust them? Do we have any other choice?
Or what happens when LGBT supporters say that lifestyle is perfectly normal; and Christians and Moslems have significant issue with that. Is that a lie? Truth? Fake News? What should social media orgs do about this?
All I can suggest, is wait and see before making rash horrible laws that will harm us worse than this crisis. There may be a clearer law that can be applied later on, with more research. (I've found that rash laws are almost never amended - DMCA, CFAA, et cetera)