I think they're referring to AN/I interactions, more than content in articles. ANI is the Administrators' Noticeboard/Incidents page, where people come to complain about more or less urgent problems they have with other users' behavior.
It's a lot of interpersonal conflict, so it has a bit of a reputation (redirects to WP:ANI include gems like "Wikipedia:CESSPOOL" and "Wikipedia:Dramaboard")