Dude, what exactly do you mean when you say corporate controlled blockchain and that he controls all the users. Can you elaborate on that? What power to they have? Would steem still work if dan an ned were hit by a bus tomorrow? This seem to be genuine cause for concerns indeed.
Click the link:
Even Steem's whitepaper admits it (Freudian slip?):
Consensus in Steem
Conceptually, the consensus algorithm adopted by Steem is similar to the consensus algorithm adopted by companies throughout the world.
But click my link for the thorough details.