That comment is quoting its parent comment in order to object to it. The parent comment was flagged and we banned the account that posted it. I'm not sure what else we should have done there.
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.
> 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.