I disagree that limiting a website for discussion on a small set of topics - an "information bubble" - is necessarily a bad thing. A web site can be designed to become a platform for a wide variety of topics (like Reddit) - or it can be designed for a small subset.
The internet is the platform that provides the variety: Hacker News for some topics, and for example RCGroups, SpaceFlightNow, or hundreds of other topical forums for others.
While it is silly to complain about "community X is going downhill", I do miss the old "information bubble" that HN was many years ago. The YC alumnus Reddit has taken over the role of a general link-sharing and discussion on every possible topic platform for every topic - but there is no longer any website (that I know of) focused on the advice, thoughts and discussion of technology startups mostly by founders of technology startups.
But for that to work you'd need a lot more restriction on signup and posting rules than currently exist, practically a closed, invitation only network. I'm not arguing that it's necessarily bad, I agree with you - the programming and technology content from professionals is why I'm here, it is unique. But there are a lot of people here who aren't startup founders, as an inevitable consequence of the site's popularity and the practically nonexistent bar on entry.
Invitation-only schemes only delay the inevitable, yet make the early members even more insufferably vocal about the gilded days of yore, the comments even more thoroughly interleaved with links to the Eternal September wiki page.
The internet is the platform that provides the variety: Hacker News for some topics, and for example RCGroups, SpaceFlightNow, or hundreds of other topical forums for others.
While it is silly to complain about "community X is going downhill", I do miss the old "information bubble" that HN was many years ago. The YC alumnus Reddit has taken over the role of a general link-sharing and discussion on every possible topic platform for every topic - but there is no longer any website (that I know of) focused on the advice, thoughts and discussion of technology startups mostly by founders of technology startups.