@realcaseyrollins

This sort of thing has been likened to evaporative cooling[1]. From a collection of particles of varying temperature, you can allow the hottest ones to escape, and the average temperature of the remaining particles will be lower even if no individual particle has cooled.

Similarly, if people aren't restricted from being hostile and insulting on a certain instance, eventually the moderates who don't like being insulted seek a less hostile environment elsewhere - but since it's not the extremists that leave, the average of the remaining members becomes more extremist. You can start with free speech and wind up with Nazis depressingly easily.

A balance has to be struck to maintain a stable community. On one hand, enough dissent must be tolerated that you're not constantly retreating from the advancing frontier of forbidden expression. On the other, you have to be willing to expel the troublemakers before they drive off your moderate members. I think @freemo and the gang are doing a pretty good job here of striking that balance.

1: https://www.lesswrong.com/posts/ZQG9cwKbct2LtmL3p/evaporative-cooling-of-group-beliefs