Elitism and differentiation aren't the same, and in particular the latter doesn't imply the former (and likewise for elitism and exclusivity). You are right about exclusivity and differentiation being effective strategies and gave good examples for how they are useful.

I am usually impressed by the ability of folks on HN to disagree while keeping the conversation civil & interesting, especially when compared with other platforms. That said, I suspect that the demographics that frequent HN represent a pretty narrow slice of humanity, and like any subculture this narrow slice of humanity is subject cultural whims and various ugly forms of groupthink and gaps in perspective that any culture on Earth is. That's specifically what rubs me the wrong way about your previous comment about "civil facts-based conversation" (and framing of people on other platforms as "riff raff").