Regular databases can be distributed across many servers. If the blockchain is private, the DMV would have unilateral control to just roll things back if they

Regular databases can be distributed across many servers. If the blockchain is private, the DMV would have unilateral control to just roll things back if they desired. All of the public mirrors would notice that but they'd have no say in it. If the public nodes did have access the DMV wouldn't be able to control the chain (and wouldn't be able to revert mass errors/failures) and they won't let things out of their control. This is absolutely just buzzword soup.