reddit is weird. About 10% of the content which is actually interesting is sunk in the flood of boring and repetitive stuff. And the community is rather bad in picking out the good posts. For example, on the astronomy subreddit, excellent photographs and great popular science articles usually struggle to compete with amateur snaphots and tabloid-like items for total laymen.
And the homogenity. Most of the time, everyone seems to have the same opinion on any topic. Everyone who dares to challenge that gets quickly killed off with negative karma.