My theory is that smart people have a mischievous side and get banned pretty quick by reddits insane moderators, so you're left with the middle of the road petty gotcha people.

HN mods are pretty lenient overall and really seem to only ban after numerous rule violations after giving numerous warnings.

Smart^ people don't get banned on Reddit they just get downvoted.

People come to HN comments to have a constructive debate, so they are less likely to downvote for disagreement. I often upvote comments I disagree with if the point is well made.

People come to Reddit to have their beliefs confirmed. The subreddit structure reduces mixing between users with different beliefs, and where that mixing does occur, e.g. on the large subreddits, it tends to turn into a downvote battle.

^ It's not really about intelligence but openness to new ideas. You can have one without the other.

[flagged]