Generated comments are not allowed on HN, and this has been the case for a long time:
https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que...Identifying generated comments is not always easy, as others have pointed out, plus we don't come close to seeing everything that gets posted. If you see a post that ought to have been moderated but hasn't been, the likeliest explanation is that we didn't see it. You can help by flagging it or emailing us at hn@ycombinator.com.
With LLM comments, there's an important distinction between legit users (who may have no idea that they're breaking a rule, especially because it isn't explicit in the guidelines yet) and accounts that appear to be posting nothing but gen-AI text. If you (anyone and everyone!) see a case of the latter, definitely please email us because we've been banning those accounts.
Even in more borderline cases, though, it's still helpful to email us because sometimes we contact the user, if we can, to let them know that we've been getting such reports. Or we might tell them we've suspended their account until we hear from them that they won't post LLM-generated or processed comments.