Earlier quoted context omitted.
The other component is that algorithmic feeds encourage echo chambers. People engage with outrage most when they are on the “same side” of it.
But what of trolling then, a sort of counter reaction to the echo chamber where large outliers enter the room and disturb the equilibrium? For my part I think it's asynchronous written debates that are the source of these problems, so even earlier than facebook. On a large massive forums, people write for themselves, not the others, and barely read the discussion. Oral debates or written rendering of them, had the ad…
The former is like a bunch of drunk grandpas mumbling to themselves in a room, the latter is like a self interested orator playing to a crowd. Asynchronous written debate can be the one of the best forms of communication. Think about Jefferson’s letters or other famous correspondence. The incentives are just wrong on boards with ranking and voting