The default state of almost every subreddit is endless meta discourse about the subreddit itself. Then there is the inevitable fracturing when some participants

The default state of almost every subreddit is endless meta discourse about the subreddit itself. Then there is the inevitable fracturing when some participants disagree, while the original sub descends into the most vapid of the commons. /r/atheism is the pinnacle example (this is a trend that becomes exaggerated the larger the sub). The subreddit approach alone does not scale. Or rather it does scale by endless manual fracturing, which is a half-assed, luddite solution.