That's what SMTs are aiming to solve. Eventually Steem itself will just be used as the bandwidth that allows you to participate in the community that has created the incentives that most align with what your looking to see as a reward system for a community.
Steem is not dependent on Steemit at all in the same way that EOS will not be dependent on a singular app that is built on it.
If you want to know about Blockchain then this post is for you surely https://steemit.com/blockchain/@fxfighter/preface-of-blockchain-part-01