I don't know, I think there needs to be some form of unambiguous BS pushback signal, a gradient that starts with minimal intrusion on discussion along the lines of "people are starting to notice that some of us are talking past our pay grade." Not saying anything at all amounts to an endorsement of penalty free bullshiting, and after enough of this the hard-won cultural expectations start to shift about what constitutes acceptable participation.

There's a spectrum between Reddit on one end, and the typical IRC channel fiefdom with its mod-permissioned voicing, invisible banhammer tripwires, and admonitions to LuRK MoAR, on the other, and I think HN is in a sweet spot/zone somewhere between those extremes, but perhaps might need an adjustment in the direction of the latter.

Downvoting/flagging somewhat furnishes this signalling, but it's too ambiguous of a signal and is often abused by people who simply want to suppress information that is perfectly valid but not to their liking.

This is where a slashdot type of lightly sentiment-coded moderation system really may be worth bringing back into fashion.