Yes, we are all here and we do not know the future, but the thing is that with the way things are going, I really do not see how the OP's painting can come into reality even in the long run.

I believe this system would have gotten even more established with some regulations by then, that the last thing the government will be thinking of is to drop out decentralized currencies because of their own use of the blockchain. Blockchain technology will help build their own form of centralized currency and things would still be just the way they are.