DPoS is by far better in terms of the resources that is used for consensus on the blockchain that use this type of algorithm, although the security of PoW is much more than DPoS because there may be gather of powerful people that are interconnected on DPoS, this may cause security threats to the blockchain.

Steemit is a social network, it was practically the first in its style. It was created to give authors ownership of the content they create

This is very true, the original content owner has her value preserved because it cannot be stolen and used by another person on the Steem blockchain without being marked plagiarism.