This is not Twitter, and the poster is utilizing a pseudo-anonymous handle, perhaps unlike on Twitter. They don't care about disseminating their beliefs here because they won't be attributed to their "real" identity.
Or maybe they're willing to disseminate some of their opinions because they trust HN to not hang, draw, and quarter them.
HN is not a black hole, information can flow out of it just as easily as it flows in. If they are careful to not disseminate their personal views on one public internet forum they should be just as cautious about voicing them on another. I believe that the pseudo-anonymity is far more important than the platform.
Opining about twitter isn't the same as commenting on AIDS in Africa. It's a stretch to call the former "political".
I think it's your opinion on the "ghetto," not twitter, that raises eyebrows.