[stelfer]

You're assuming that the reward function is giving you the community you want. In reality the reward function is to maximize engagement, which is a proxy for ad revenue. When there's an asymmetry in engagement dynamics then the whole thing drifts. The mass fallacy here is that FB is trying to build communities.

[b_ocu]

The "engagement" that you're talking about is causing other people to leave, so I don't know how that works in FB's advantage here.

If they really wanted to maximize "engagement" they would actually hide all of the political posts and rage inducing comments and show nothing but cat pictures.