At the end of the day, it is the moderators who maintain and control the community. They control what users even see, so it’s not fair to say a community is made by the average user, the average user is completely silent. I would rather competing communities over every community being at the whim of the masses. The masses are easy to misguide.
On the note of traffic, I still browse Reddit because it has niche communities that I want to interact with. However, I don’t comment, post, or even up/downvote anymore. My interaction is now purely browsing, and I imagine it may be similar for other once-power users.