So...I can't come up with a better way to put this: do you really think that there are intellectually satisfying, civil discussions to be had when your existence is a matter of debate? Like... 'hga wasn't alone. You know that. He was just an idiot who went straight at it straight instead of hiding behind cites of The Bell Curve, instead of "but why should there be programs for black people or women?". I get your focus on "civil, substantiative conversation" and I respect that, but you gotta know as well as anyone that harm happens behind the "civil, substantiative conversation" of just-asking-questions and oh-it-can't-be-that-bad,-can-it?, the soup of toxic sexism and racism that's all over here over the last year or two. The functional result of "no politics" is that that won't be challenged, not that it'll go away. I agree with 'tptacek when he says that most political comments on HN are alt-right trolls; "hey guys, subtext rather than text" leaves a lot of shadows.
You and I are effectively re-litigating the same arguments that have come up in many other places. What would be awesome and a change of pace would be to learn what HN plans to do to make itself civil and welcoming to underrepresented folks, if that's the ethos you want to have. And you say you do, so I believe you. I mean, hell, I'd love to help out if I can; you have a bigger stake, but you're sure not the only person who thinks there's something worth having here.
(As far as other places on the internet--I have a few that come to mind. Open ones, but not ones on which I want to sic the jerkier part of HN just to prove a point in an argument. Shoot me an email if you're curious.)