Personally I would hold up HN's moderation up as an example of how to preserve civility without suppressing ideas. I don't think you can "do better" for one group without doing worse for another.

Upon further digging, I think the complainant is not fully mentally well.

> and we banned the account that posted it I'm not sure what else we should have done there.

Take a moderator action at the time and not a month later?

Good moderation requires time for deliberation and careful judgement. Hasty decisions will lead to bad decisions and given the huge volume of comments that Hacker News gets, Dan does a sterling job.