Unmoderated/fully-self-moderated free speech for political content trends towards extreme ends of either stance.

I've seen it repeatedly in reddit, 4chan and others. Reddit attempts to walk the balance of site-moderation vs user-moderated and it's extremely difficult on that knife edge.

The hope with ZH that it would span the political divide and allow proper discourse and exchange of ideas from both/any side of thinking.

But without moderation, it trends towards mud-slinging, vitriol where arguments become so divided that it's no longer discourse.