Not all actors are participating in online conversations in good faith. Meaning, a big part of the problem are trolls and propagandist antagonizing and encouraging division. Part of the solution has to be stopping them.
Lots of other comments here say it’s just the old trolls at scale, but I agree with you. There is propaganda at such a scale that it’s hard to miss and some is very hard to spot. I don’t remember people in the US being so likely to repeat Russian propaganda in the past. I routinely have people repeat Russian-twisted, false accounts of historical facts to me! This isn’t the old problems at scale.
Edit-just this morning the news reports Republican senators being afraid for their families well beings if they counter Trump. Unthinkable just 4 years ago.
The trouble with this solution is that not all actors wanting to stop people from participating in online conversations are doing so in good faith, even if they frame it in convincing-sounding language about trolls and propaganda. In fact, I'd say that this is probably a massive magnet to every single bad-faith actor out there, and given the us-vs-them climate it produces there's probably no way of stopping those bad actors.