I agree that HN is heavily moderated, but from what I've seen the comment moderation is more focused on maintaining civility and tone. I think dang and friends will let you say controversial things as long as they're framed in a productive way and you aren't a jerk about it (and as long as you don't commit the sin of editorializing a post title!)

I think that's a stark contrast with reddit, where being a dick is often excused if one has the right ideology. Not to mention that many subreddits (especially, but not exclusively, the political ones) have become carefully maintained echo chambers thanks rules against disagreeing with even a single facet of the "correct" beliefs. r/The_Donald even had an explicit "no dissent" rule.