Oppressive regimes usually /employ/ people to do the propaganda. HN could be just large or influential enough that it gets on the radar at some tiny office, and

Oppressive regimes usually /employ/ people to do the propaganda. HN could be just large or influential enough that it gets on the radar at some tiny office, and there might be people whose task is to watch it and kick in with comments/upvotes/downvotes when necessary. It does not have to be many people, and it can be only a tiny part of their daily watch on larger media. Moderators would know better about whether this is true on this particular site, but this happens regularly on mainstream channels.