I think that Steemit can be controlled as well, albeit in a much more indirect way. Whereas other sites can just remove you from their platform, a poster and or post on steemit can't be completely removed. However, these posts can still be heavily censured if a group with more money/STEEM chooses to do so. If you go below 0 rep or are constantly heavily downvoted then your posts are practically invisible. As an avenue of truth, steemit is still severely flawed.