Why does it have to be the harassed that have to seek a haven? This is a new WORLDWIDE space. Wouldn't it be a much better space if those that want to harass or be harassed are the ones that have to go find somewhere else to do it than on servers where everyone else manages to get along?
I got an in-your-face porn picture in my federated feed the other day. Innocent server - very not innocent picture. I would definitely like it if I could block that server that allow porn, to be honest.
I guess I am asking what is bad enough for enough people that it should be on separate servers. i would say it should be something (bad?) people DO on here, not what people ARE. If you do post porn, do harass/bully, do post fake news - those are my suggestions.