Or are we just talking about banning the lame “durr, I asked cGPT and here’s what it said” responses? Those get downvoted anyway because they got boring real fast, especially since cGPT is free and open to all.
But I think this is more about preventing/limiting karma gain of an account, potentially posting/commenting limits and similar stuff.
I.e. it's more about migating the (assumed negative) effect a few people abusing comment generation could have then it is about punishing people.
You can also prevent farming high karma by just preventing flagged accounts from getting karma, given the nature of karma HN could also delay accrediting karma to accounts in general which would mean that for farmers it would take much longer to realize that they got flagged and in turn wast resources.