Fear is a key driver (period). I just heard this on the radio. They analyzed what pulls people in and it’s fear. Fear also keeps people lingering longer. I didn’t hear enough to explain it (I got to my destination before the show was over). Putting it together with other things I’ve heard, the algorithms that are tuned to keep people engaged on the site skill natually choose things that stoke fear and that is probably the same thing that the facist propaganda is promoting, too.