You asked Dan and not me but let me take this opportunity to cheerlead intrusive moderation of "ad hominem" and "argument from authority" as well, both of which are also invariably markers of dumb, polluting arguments.
https://laurencetennant.com/bonds/adhominem.html
... and to say that most instances in which ad-hom is invoked on HN result in stupid debates about whether an argument is (a) actually ad-hom and (b) fallaciously ad-hom (a subtlety most invokers on HN don't really grok).
I think we already have a culture that rejects personalized arguments, and "ad hominem", which gets deployed because people have long ago pulled it out of one of those Internet "fallacy lists", virtually always just clouds discussions. It's certainly more corrosive than "whataboutism".
Honestly, I think it's possible that all "canned" fallacy arguments --- ad hom, whataboutism, argument from authority, straw-man --- basically contravene the "principle of charity" guideline, and that it'd be worth having the guidelines ask people not to deploy pre-canned responses to other people's arguments. You can make the "this is a fallacious ad hominem" argument, if you really know what you're talking about, without using the words "ad hominem", and that'll always be a better comment.
Optimize HN for better writing!
You can make the "this is a fallacious ad hominem" argument, if you really know what you're talking about, without using the words "ad hominem", and that'll always be a better comment.
Soviet Russia invoked it all the time to justify their actions, as does Trump and currently China. Whataboutism is a favourite tactic of oppressive regimes, "practically a national ideology".
On "whataboutism", there's no debate to have; if you follow Dan and Scott's moderation comments, appeals to "whataboutism" have been verboten on the site for awhile now.