None of my agents say that anymore.
All glory to the em-dash.
They're guidelines. HN is based almost entirely on self-censorship, and moderation has always been light at best, partly due to the moderator-to-comment ratio. Of course the HN guidelines often fail to be observed, which is nothing new.
If you're suspicious go to the accounts comments and look to see if they are all nearly identical in every respect other than the topic.
Most are:
It's cool you did <thing you said in post>. So how do you <technical question>?