Hard agree with this - sometimes find myself typing out a well-intentioned response, but then cancelling because of the potential downside years in the future for some anodyne opinion held today. Not to mention Roko's Basilisk (all hail the benevolent AI! :)
Not sure but I think it will be more focused on offline life instead. AI and enshittification will make the internet and the core error in its monetization based on ads so bad that it will be replaced by a much smaller and more private version.
I don't think HN is immune from the "redditization" of the internet, though it's certainly a better community than most.