@ariadne @eff I have no comment on the technical aspects (you clearly have a much better grasp on that than I do), but I'd like to add two points that might be persuasive to some:

1. If the concern is "fascists will use this principle against good speech in the future" - since when do fascists care about principles?
2. The speech in this case - harassment and doxxing - is itself the harm that needs to be stopped. So yes, there is a real, actionable difference between KF and other websites.