I chalk it down to HN being positive (and me being polite and not needlessly provocative), and I also try to help others who have been targeted by the downvote & flag squad as long as what they have said is somehow reasonable.
For a long time, I've been an avid HN reader. However, one day, months ago, I noticed that majority of posts in most threads I was reading on HN started with a variant of "You are wrong". It may be in some form that does not make it immediately apparent but once I noticed the pattern, it was hard to unsee it. After this, I just stop reading threads which have a lot of this and in general, I've found that the few threads that remain make for (relatively) pleasant reading.
I haven't yet found something better than HN though. So, I chose to stick around for now.
But in a discussion where you have an upvote button, there are basically only two follow-ups to an assertion which remain on topic: "you're wrong", or "you're right, and also". Anyone who wants to +1 will just click the upvote button.
"Me too" posts aren't worth posting so if I have nothing to add I'll +1 the comment I agree most with/is most accurate to my knowledge and leave it at that. The result being I have a lot more "You're wrong, here's why..." or "I disagree with [something said]" than I have posts saying "You're right, and also..." since I don't always have something to add. It makes me seem really negative - since nobody can see all the comments I've +1'd. Multiply that by every user on the site and things look more negative than they are.
I use "-1" for "You're horribly wrong and I don't have time to correct you (though sometimes I have time and will)" and "Trolling/Vapid posts". If someone is "a little wrong" I don't -1 them and will just post a minor correction.
If you have a belief that can't survive HN downvotes, to the point where you'll hide it simply to avoid those votes, you should consider how sincerely you hold those beliefs.
People with less karma need to avoid downvotes and flags because it affects how they can use the site - it affects the rate limiting they get.
(And because they don't know that they can email dang if they think they've been unfairly flagged.)
"Hellbanning" is a form of banning where the site takes steps to avoid tipping you off that you've been banned. It's ostensibly a defense against spammers and trolls, who will create new accounts after being banned.
For the past couple years, bans on HN are announced publicly. They're not automatic; the moderators do it directly. It's not based on your karma.
For the most part. We don't do so for spammers or (sometimes) serial trolls.
Top-level comments that are literally seconds old are typically posted about 2/3 down the page. None of my votes appear to actually count. It's been this way for several months.
I'm used to it, but it's still very annoying and I wish HN would actually acknowledge they do this.
I'm pretty sure that's not it at all[1]. I can see (and personally do these days) avoid[2] certain types of conversations because of all the down votes. It has nothing to do with not sincerely holding the belief, and it has everything to do with not wanting to expend the energy on comments that aren't actually going to be seen[3]. As you know, as a comment is down voted it turn grayer and grayer. Plus, if you're not as articulate as you wish you were, you are just going to feel frustrated that you couldn't get your point across.
This board, for most, takes up free time, and people tend to want to enjoy their free time.
1) in fact, that statement does rankle the feathers a bit - I've heard a variation that was meant to silence people
2) not very successfully at times
I have difficulties thinking of HN in the singular - from what I can tell it is a group of people with pretty different views on most things. I don't think people get downvoted for expressing different views - pretty sure the times I have been downvoted it is because I've said something crass, irrelevant or just plain wrong!
It's such a relief to read this! Seems so obvious, but the trope of anthropomorphizing the community grows like weeds.