It's difficult to reply to this because there are lots of moving, intertwining parts. I'll label them, I guess

  1) I didn't assume political apathy, but I did assume apathy about this particular case.
  2) His responses suggested that he was somewhat concerned with politics outside of HN.
  3) My use of "these sorts of issues" did suggest that I meant politics in general, but I meant *this* brand.
  4) I did not suggest that HN was a vehicle for political awareness in general, but rather than this brand of politics is well-placed on HN.
  5) I also suggested that this particular brand of politics do belong on HN given its criteria.

I realize this isn't my best writing, but I'm running on very little sleep and I don't have the energy for the dozen proofreadings and rewordings that I normally give my posts. I hope that my meaning can be accurately discerned.