Reddit was briefly a pretty cool place when a bunch of people discovered it from one of PG's essays. He'd post from time to time, as would a bunch of other people who were basically "the HN set". My guess is that if you looked at the early users of HN and of reddit, you'd find a significant number in common.

A lot of hackers have a libertarian bent, and that really started to come out in Reddit's political discussions, which started attracting more people interested mostly in politics and some of the various 'outrage' stories being posted about police abuse and things of that ilk.

IIRC, that was the trigger for PG to create HN, which is much more focused in its approach.

Yet another reason why I loathe politics on this site.