What do you think a normal person thinks when he sees a witch being burned?

Normal as in "average" or normal as in some kind of healthy & moral?

The average person puts their pitch fork back down and enjoys the bonding experience that a successful hunt brings to the community. The out-group isn't just persecuted because they are different, the whole process also helps confirm the unity of the in-group.

Historically speaking, "Good riddance."

This is an interesting point! However, I also note that there is a limited number of “genuine civil libertarians” (or, of people in general I guess), so I am not sure that having more of these would necessarily improve the ratios between the two within any particular town/site ?

Also if people are spread sufficiently thin, some of the sites will die from “no one is using this”, I think.

I don’t know how this all balances out, but what you brought up does seem like an important force/mechanism to take into account. So, I’ll say “Further work is needed in order to understand the behavior in this area.”, haha.

I'd guess that the need for genuine civil libertarians would go down with the witch density. The super majority of people is probably fine with seeing one witch per day, but they really don't want to live anywhere where they feel surrounded by witches.

The dynamics involved in city districts rising and falling and rising again might be similar. Online communities lack the rent-dynamic however. A "difficult" part of town gets more attractive because the rent is much cheaper. I don't know whether there's anything equivalent in online communities that would "gentrify" a toxic community.