[robgibbons]

Responsive is really not difficult, to the point that it is easy. And I always advocate 'doing it by default' because it's actually more of a pain to refactor later. Basically you just have to understand floats, and using fluid design in contrast to fixed-width/absolute elements.

That said, I'm satisfied by the justification: HN lacks an API, so lots of people have built apps that scrape the frontend markup. It would break many apps overnight to just flip the switch.