I've noticed most HN comments transformed from being discussions about the _content_ of the article to comments discussing the _topic_ of the article being posted, not sure if this is healthy, but the risk is HN becoming an echo chamber where people discuss opinions, and the posts becoming just topic triggers. We'll see how it evolves.
There are lots of little rules in place to minimize the damage of this (like no memes, jokes, pics, etc.; HN actively discourages clickbait), but it can't force people to actually read the articles before responding. And, one doesn't have to read the articles to vote, either (again, HN mitigates that problem somewhat by requiring a minimum level of upvotes before being able to vote, etc.).
It's hard to have a substantive conversation online when so many of the incentives are for responding quickly (and probably without going too far against popular opinion within whatever community you're in).