Look at my other comment in this thread on the "drove someone to suicide" aspect. I'm totally neutral, never heard of KF before today. It does look like that's true on some level - the person in question did say to KF "remove a thread about me or I'll kill myself" and appears to have done so, but it's a more complicated story than that. The person in question was clearly a major suicide risk for a long time independent of KF. It's quite possible they'd have done so whether KF ever existed or not, as by their own telling they were totally socially isolated, had no friends, regretted how they'd spent their life, their entire existence was tied up in their internet identity, they were diagnosed with several mental disorders for which they had been taking many different drugs, and was doing a "DIY" gender transition using HRT against their own doctor's advice. The KF thread in question was mostly a record of this person's own online postings (which were all pseudonymous!).

The underlying issue here seems like a really complicated and socially tricky one - how should someone respond to a demand of the form "remove evidence of my past online activity or else I'll kill myself". It's probably not specific to KF. Theoretically archive.org could face the exact same situation.