I do think it comes at a cost to the rest of the community, though, when so many people participating in a technical community don't really understand much of the discussion.
Hacker News helps mitigate this through the continual involvement of PG and YC. Because there are a group of experienced technical people who are grounded to the site, it helps keep quality up. While I have noticed a slight decline in the site, it's far less than I noticed with Digg, Slashdot, or Reddit.
From what you two are saying a person like myself, who is just starting out and therefore not writing much in the way of code or blogposts, should not be reading HN because I can't join the discussion with anything but questions?
What about likeminded people discussing a topic that interests them? Is there no room for that?
lurk moar.
But since the point of HN seems to be "sponge learning" at large (of course, different levels of sponge learning), I don't see any sane way of moderating what should be worthy of HN from what should be asked or posted elsewhere, so long as it has the feel and common interests of the community, and "gratifies one's intellectual curiosity."
What worries me is the voting, which is anonymous and hard to self-regulate. Take a recent, heavily-technical article that made the front-page: http://news.ycombinator.com/item?id=2730286 How qualified is someone (who just learned that something like Coffeescript is even possible) to judge the technical content of a blog post about how GCC shuffles references between the stack and registers, or the discussion around said blog post?