Yes. You're right - the transparency is really good on steemit. But what I mean is that even on steemit people can create new accounts (via cli, steemd or anonym service) - transfer funds onto it and then upvote the posts which support their opinion - which will then become hot and trending.
So in my opinion - what happened on reddit - can also happen on steemit. Posts can't be deleted, but they can be swept under the mat.
But the suspicion of new accounts not being linked to anyone verified or real quickly kill their effectivity of trying to manipulate discussion with votes.