Well in this case, Steem (the company) owns Steemit. Even though writers and readers can earn money from the platform, ultimately it's not ours. So Steem decides what content they want on the site. As you say, they may decide not to meddle at all. Personally I think they ought to try and guide the level of content; e.g. find ways to reward the honest grafters, and other ways to dissuade the dodgy stuff. #my2cents