I recently changed my mind about the quality of the producers and consumers on HN.
Too often, people talk past each other.
Too often, people nitpick like http://news.ycombinator.com/item?id=782752
Too often, edw519 gets upvotes for 'pithy' statements like http://news.ycombinator.com/item?id=864709
Too often, reposts galore, and even worse, from techcrunch: http://news.ycombinator.com/item?id=743735
Too much non-contributing irrelevant self-promotion: http://news.ycombinator.com/submitted?id=kkleiner http://news.ycombinator.com/threads?id=kkleiner
Too often, votes are based on... zealotry? http://news.ycombinator.com/item?id=902804 Why would jrockway get downvoted for answering a question as to why OSX didn't merit the Apple Tax for his purposes?
HN is useful for the domain knowledge and experience of some notable fellows, but a lot of the active user base dampens a lot of the remaining signal.
I look at people's time on the site when they say the community has changed because I want to know if they're contributing or consuming.
This is a community, and it can be reasoned with by anybody, as long as they take the time to try and do it.
I think for the most part, the responses on the threads you linked showed that. Sometimes people will reflexively downvote people because of a perceived slight. I have a feeling that some of the early voting trains get undone as the day goes on.
That being said, I'm sure I've personally contributed a significant amount of noise to conversations here, but if I wanted pure signal I'd probably spend a lot more time on places like LtU. The value of this place is the conversations, far more than the links (in my opinion).
I used to flag them consistently but I just gave up, so kkleiner wins that round and gets to spam as much as he wants.
Flagging to keep out the spam is a way of doing community service, if the feeling is that it is for nothing or possibly even ignored (PG hinted that people that flag a lot have their flaggings discarded) makes me much less inclined to do that work.