In another comment, you said that HN isn't siloed[1]. I think otherwise, there's definitely a certain vibe of groupthink going on, which changes ever so slightly depending on the time of day, but mostly has strong common undercurrents of what are acceptable lines of thoughts and what are not in the greater HN community. And then within a given timezone, there are thought-cliques that share common counter-positions.
I would say, HN is siloed, it just has a few silos.
This seems to be true. I noticed on my comments I get pretty consistent waves of upvotes or downvotes depending on the time of the day. My comments are usually pretty politicized and polarizing, so my guess must be that the US wave likes my content less and the European wave likes it more.