To deviate from this model, we could encrypt our content before posting it to Steem. If we wanted to have it accessible only via our own personal website so as to be the only entity capable of monetizing it through ads, we would only have to encrypt it and have our website decrypt it after being pulled from Steem. We could only leave a teaser unencrypted and a link to our own website on which could be used as a Steem front end to allow Steem users to comment on our posts. I have actually seen something somewhat like this done on a few occasion on Steem. I have seen Steem posts that were a summary of a longer article on another website behind a paywall. I would personally never upvote any such summary as the reward pool is a common resource in which case the content should be, too, as in available to anyone for free.
What do you think about what ownership of content means on Steem?