We're much, much worse. "Most communities" are built around consensus. Show up at your Facebook group organized around your favorite hobby and you'll find that everyone has a bunch of similar opinions about most things, and that's the way most people like it. Walk off the reservation and try to pick fights over something controversial and you'll find the community walks away.
That sounds bad, right? What if consensus is wrong? Don't we need free thinkers?!
HN is an enclave of antisocial nerds[1] who think they're smarter than the rest of society. We live for disagreement. Discovering that we disagree with our peers isn't a mark of shame, it's evidence that we've discovered a Magical Great Truth, that our "peers" at HN are all sheep, and that we're therefore smarter than the herd.
Sure, Facebook fishing groups or knitting sites or whatever breed senseless group think. But on the whole "group think" usually works out pretty well and keeps people from wandering off into the scarier weeds of the thoughtscape.
HN? We breed radicals. And therefore we're more susceptible to deliberately radicalizing sockpuppetry, not less.
[1] To wit: we're basically 4chan but with an older demographic and industry cred.