The article itself was a bit disappointing because it focused on political issues. In my opinion the strength of HN in this regard is that it is both a "sjw cesspool" and a "haven for alt-right", as evidenced by the fact that a comment on a controversial topic can easily float near zero points while raking in both upvotes and downvotes. And even those who refer to it as "the orange site" still come back and comment. In other words, HN may be an echo chamber but it is a pretty big one with a lot of voices in it.
I definitely want to give credit to dang and sctb for making it that way. It could have gone differently. In particular, the no-politics argument is basically a fancy way of saying "nothing that challenges the status quo please". [1] I really appreciate them trying to keep the forum in a state where these discussion can at least happen. I would have left long ago if flagging had continued to be used to kill topics.
[1] See, e.g., Prof Ichikawa on how skepticism gets misused to defend the status quo: https://twitter.com/jichikawa/status/1134323822096658433
Flagging is frequently used to kill topics still. Climate change articles are still flagged mercilessly, before any discussion starts and without regard for the high-quality of the articles.
dang as a moderator has specifically said that articles about Russia hacking elections are penalized prior to any votes or comments starting (edit: I believe this particular issue is done by the 'moderators' themselves manually or through a filter, not through user-flags. they are not just moderating discussion, they are filtering which topics you see in the first place, on their own).
The discussion here is framed by people who do not want to talk about certain interesting Hacker and Startup related issues, like global climate change or the stability of democracy with technology.
Flags are a common tool used by the community here to shape the discussion before it starts, hiding topics entirely from view that the community would otherwise vote and discuss.