It doesn't have any pressures to make money, in fact it's basically a free place for PR and advertising jobs for portfolio companies
HN is somewhat unique in its lastingness, and seems to have found a sweet spot in growth rate over the years that allows them to stave off the 3 things that will kill a website like this: silence, negativity, and grift. Most websites are so scared of the first one that they'll compromise on the second and third. Moderation is hard. Surely a large of dose of luck is also involved.
A lot of other Hacker News equivalents don't have that, and hence end up being just another internet forum in a list of millions.
There's also probably the fact that the format works better for engineers than it does designers or artists or athletes or musicians, since the former tend to be more of a fan of 'simple' websites with utilitarian designs. A lot of clones try to copy the Hacker News style, only to realise that their target audience finds the layout ugly and offputting.
Fake news and unpopular opinions were also really big at one time. FB killed them, mostly by adjusting visibility of some posts more than others or burying the unreliable sites. It's also why people post links in comments though.
HN is a little different though - everyone shares the same "feed". Most social media show you what it thinks you want to hear. Whatever goes viral on HN is the same for everyone else. So you're also likely to be sitting next to someone with a political opinion you abhor. There's silent downvotes on certain trigger words, but in a sense that works too, because people just avoid topics that the community doesn't like.
I feel like Ask HN is also a vent for negativity, while Show HN is a vent for optimism and self-promotion.