I've never heard of this, please elaborate. What are the dividing topics?

I guess the reports in English usually refer to the "human flesh search engine":

https://en.wikipedia.org/wiki/Human_flesh_search_engine

From the description, this might encompass phenomena that we would call both coordinated harassment and public shaming, and maybe the original article by Megan McArdle also means to encompass both, though it seems to have more focus on public shaming.