[pjc50]

"Echo chamber" seems to be the wrong word; the problem seems to be more like who gets the megaphone. The article talks about "superposters".

> "even if only a minority of users express vehement anti-refugee views, once they dominate the newsfeed, this can have consequences for everyone else"

Do this kind of thing in the real world and generally it's met with silence; uncomfortable, disapproving silence. Or people organise tiny pro-racist demos and are outnumbered by counter-protestors.

On the internet, a silent majority is invisible. To stop these people dominating the newsfeed, you have to actively drown them out, which means being louder and more effectively clickbaity for the algorithm that decides how loud you get to be.

(We should also not over-estimate the mainstream; it's probably very mainstream to have misgivings about refugees, but that's a long way from actual violence.)