Unfortunately for Reddit, Reddit seems tailor made for federation. It’s nothing but topical sub-sites that already have administrators and audiences.
@rcade @murtaugh because you're a longtime reddit user, not a new one. You know what you want out of the service and where to get it, others don't and need that kind of algorithmic direction.
I think this is one of the challenges for mastodon, too, to be clear. It's a great set of tools for people who know what they want from a microblogging service, and nothing for anyone who has a less well defined set of needs.