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I would say any content adds value; interactions, building communities. Anything that is created. It doesn't matter the topic. Even using the steem blockchain to store encrypted messages adds value.

The governing is just an economic and social incentive to keep adding to the community.

Extracting value would be using content in some way and also extracting economic value from the system by converting to fiat.
To be clear I am not against that either unless someone is taking advantage at others expense.