Is it though? My impression of HN is that debate isn't encouraged. Heck, discussion is basically discouraged. HN intentionally makes it more difficult to see if people responded to your comment to prevent people from constantly trying to defend their internet honor. However, back and forth discussion is important for debating ideas. HN guidelines specifically ask readers: "Please don't use Hacker News for political or ideological battle"

HN seems more geared towards "intellectual curiosity" and the discovery of new ideas. It doesn't seem tailor-made for rational debates, or specifically designed with debate in mind. I've yet to see a platform that attempts it (haven't looked into the posted site either).