Even in the hobbies, particularly sports, subreddits I see a lot of narrow mindedness that I don't see in other forums for the same activities. Like asking how to do X type of cycling, the top comment will be some exhortation on how you must do ABC with Z bike or you will die. Versus bikeforums.net, where people will chime in with a more "anything goes" attitude, and seem to have greater depth and breadth of experience.
Indeed. I had plenty of positive experiences on Reddit, but many subreddits are very chaotic relative to how popular the subject is and who ended up there. The voting system just doesn't scale well in my opinion.