People don't write their blog posts exclusively for HN.
Just because someone other than the original author posted an item to HN does not mean the original author should be held to account for some perceived slight to this site.
No, the implication is that if the rules of community are no personal attacks, making those personal attacks in another venue where it's still clearly and identifiably about the community/member is still a violation of the rules of community.
I can't see anywhere in the guidelines where there is any rule about not posting anything off-site relating to HN, or not identifying members of the community.
There isn't even a rule against what you are choosing to label a 'personal attack', but looks reasonably civil to me.
Even if there were such a rule, attempting to silence dissent outside the communities own spaces is behavior typical of a cult or authoritarian regime. A healthy community isn't afraid of people thinking and saying things that some of its members don't like.
I'm not saying silence dissent outside HN. People are free to post on their blogs whatever they want. If they are making a personal attack against someone on HN on their personal blog, the link to that blog post should be blocked from this site and the user absolutely warned/banned if they themselves share it.
I've had run-ins with "high profile" people here on HN, as well as a tiff with Ycombinator. Turns out, the high profiles can be disgusting, nasty, brutish, and rude: the same way you gain status in the 'Valley. How do you defend against it? Well, you can't here. Your account is shit-canned, hellbanned, modded to death, or openly insulted and berated.
So yes, users take to other channels. That's what I did when I hacked the Thalmic Myo. Didn't know it was a YC venture. Company was crippling hardware for getting more money (surprise!). Posts here went poof. Fortunately Hackaday took it and ran with it. Took around 5 hours for Thalmic to make a statement and change their whole viewpoint, for that I am glad.
But no user Ms, don't expect much changes to be made here with regards to bad policy and bad discussion; for they will turn around and do the opposite they recommended just days prior.
It's actually a social power attack, not a personal one. The "attack" (it's very hard to find any language in the post that could be considered an attack) is that patio11's advice is not great for this specific case. It may look like a personal attack because why would someone post off-site just to comment on another person's comments?
The answer is, social power and the threat of in-group reprisals. If you challenge an extremely popular person's opinion, the in-group will attack you, because you basically just challenged their whole group mentality that this person is implicitly trustworthy and correct no matter what.
However, both of them have potentially bad advice, because they have a very small portion of a much longer story, and they both think they have the solution to something which may be much more complex. patio11's is more "nuclear", while the open mic author's is more "hiring is difficult and the incident may not be as horrible as it sounds so let's see if disciplinary action helps". Neither may apply, depending on all the left-out details.
Just because someone other than the original author posted an item to HN does not mean the original author should be held to account for some perceived slight to this site.