Reddit has a different weighting on this stuff and as a result you get a different culture, and these even differ between sub-reddits, but have the signature of a different weighting system, and a greater ability for sock puppeting. I don't think one is better or worse, just that these trade offs are there and have to happen.
It's not the only example though. In my comment history you will see another set of discussions that are essentially the same (but a few months apart) where I'm arguing that autopilot doesn't imply self driving. One was a discussion which seemed balanced by votes (I probably lost). The other descended into users calling me a "smug pedant" and a lot of bullying, about -35 karma (and ultimately my first banning). I was pretty disillusioned by the experience and couldn't really work out what was so different, and why I was banned for defending my point of view despite the other peoples behaviours.
I would never have interpreted your comment as a flame btw - such is the nature of robust discussion, but I appreciate you pointing it out. I think too often people take an intellectual assault on an idea as a personal assault. They are different, and I welcome them despite the pride I lose hopefully learning a lesson. I'm always genuinely grateful of the time a commenter takes to put me in my place, but usually it is just "pedant" and down vote.
HN serves a rather specific goal, it is basically PG/YC's playground. This community will never be allowed to deviate much from their interests. That's a given you know pretty much when you sign up though.
At the very least Reddit is far more broad. So of course you're going to find a subreddit where you feel you belong. Some just might have to search further. In a way that's an easy statement to make though akin to "If you date enough people, you'll eventually find your soulmate."
Anyway, the comparison is moot due to the size difference. Its more fair to compare subreddits or groups of subreddits (how does that work?) with HN. Such as say startup-related subreddits.
AFAIK you can be punished even if you are part of the groupthink.
Which is good IMO.