I don't buy the legitimacy of private blockchains for a second. We all know that the data structure of blockchain is not the best in the world. The advantage to it is that it is immutable and makes censorship much more difficult. Plus, on the financial side, it does remove 3rd party counter risk.

Any blockchain that is private is subject to the entities that control it. We see with Steemit how being at the mercy of their financial solvency is dangerous.

And for those who the entities mentioned using private chain have so much money, look up what happened to AIG.