For me the coolest thing about HN is the breadth of experts here for any (even niche) tech field. This allows for in depth understanding of new products (when someone who actually worked on the team making it is here) or calling out conspiracy theories about why some company shut down some product (because they have inside knowledge and can actually explain the reasoning).

I can't count how many times I've read 'I work on the team that built that' with some new insights or opinions just sitting nested in a comment chain 4 levels deep.