"This seems to be the sort of thing that would come to the top on its own."
Maybe, but not in that time period.
"Also, this isn't Reddit. The commuity and moderation are pretty different here."
If anything Reddit does more to defend against this sort of thing.
"do big advertisers even know about us?"
I have seen so many posts on the top of hn talking about "the hn effect" It is ridiculous to think that people in pr and marketing aren't paying attention to that, while gaming product hunt and reddit.
I own a software studio that makes software and I am noticing how vulnerable HN is. Other people have obviously noticed as well.
Also, this isn't Reddit. The commuity and moderation are pretty different here.
In addition, do big advertisers even know about us? We're pretty niche, and not all that well recognized outside of the programming community.