They crossed a long time ago! They should have worked like phone lines, just a medium
Social media is very public. I'd say it's closer to radio than telephone.
This is part of the "mistake" of the social media companies. Rather than emphasizing cohesive friend groups, they (particularly Facebook) defaulted everything to be as widely visible as possible.
For me, democracy has 4 pillars that must be independent, and currently are not is most countries: executive, legislative, judicial and media. The 4th one is controversial but nonetheless necessary for the country to be a democracy.
Democracy without equal speech time for all parties isn’t a democracy – it is like Singapore, a single-party democracy.
Finally, we must have a population who is educated enough to read ambiant news and distinguish false from truth. If you say that is impossible, you advocate for the people’s decision being taken by a central organization, aka not people’s decision. Educating people enough is entirely possible; For example people are routinely exposed to scam and a rule of life is never to fall down into scam. Only a few % of pop fall for it and it is fine. Democracy is based on the same people. You precisely shouldn’t prevent people from being exposed to fake news, otherwise they become ultra gullible (which may be what you want, in the end...).
All in all, what leftists call fake news or debunked news are often... falsely debunked, by journalists who try to present alternative facts, which the people are getting tired of. It’s ok, we understand they don’t want to lose grip of the leadership.
From a legal/political standpoint SM is on new ground: a privately owned (i.e. non government) platform but with massive reach. Free speech laws are aimed at the government so should they be applied to private companies? I can understand both sides and I don't think there's an obvious solution.
Yes, they should have just been private point-to-point communication mechanisms. Unfortunately, they decided to be broadcasters instead.
I'm kidding, but ad supported commercial promotion (broadcast) of speech (for additional profit/engagement) is pretty far from what I think the framers of the constitution meant as Free Speech (of the individual)... but then the Supreme Court has decided that money is speech (and corporations are people) so it doesn't matter what I think.