Ask HN: What are the things that hacker news were wrong about?
Dropbox is the first thing that comes to mind. What are the other things/tech that hacker news got wrong?
Drew Houston even said in an interview (can't recall which) that the response from HN was all the motivation he needed to keep going. It's almost certainly the biggest reason his YC application was accepted, after having been rejected on his previous project and shewed out of the office when trying to demo Dropbox to Paul Graham.
The ones that HN was wrong about are the ones that got ignored. Airbnb is probably the biggest example IIRC. Keep in mind that it's somewhat difficult to judge vote counts historically because of how much the site has grown over time.