A discussion forum similar to, say, Something Awful (or indeed HN), with a focus on mocking online misbehaviour and a reputation for unpopular political views.
Pretty accurate. You make yourself a name suing a waxing salon for not waxing your balls, you get a KF thread. You harass a github project for accepting contributions from a hardcore Christian, you get a KF thread. You declare "everything is racist, everything is sexist, everything is homophobic and you need to point it all out", you get a KF thread.
One of the three suicides seems to have not happened at all (would have been reported to the US consul in Japan), two others were attributed to posts that did not comply to KF moderation standards, were created by freshly registered users and were removed much faster than similar stuff typically remains visible on Twitter of Facebook.
Thought experiment: if KF founder committed suicide, would you demand deplatforming MotherJones?