I'm genuinely curious

I wonder - based on your comments it feels like you've already made up your mind.

How do you implement this kind of "blocking of demonstrably false information" without getting it wrong in some cases

Great question --- did you perhaps not understand or look up the famous Latin reference I mentioned which explicitly recognizes this concern.

The thing is - you're looking for binary answers in a world that is a continuum.

An advertising company which works as a social media platform for billions doesn't have conversation? Are you serious?

Yes --- a conversation requires a two way dialog. The "conversations" among small groups of people who share a facebook wall (for example) is completely drowned out by paid one-way advertisements that are blasted at large numbers of people. Worse --- far too many people are swayed by their own confirmation bias, selection bias, etc and so are not even open to a conversation. For conversations to be successful, participants must be open to the possibility that their position is wrong. Sadly, that ain't happening much these days. Heck, even the voting system on Reddit is driven by whether people like (or not what somebody says) but ignores completely the veracity of what they say. That is also not a conversation!