When corporate bylaws are written in code, you can replace a single legal entity with thousands of former employees operating as sole proprietorships.
Like I said, it depends on how you define "the blockchain". Many problems don't involve an open set of untrusted peers, and many problems don't require proof-of-work. So if you include those in the definition, then the blockchain isn't appropriate for a lot of those problems. And if you exclude those aspects, then what do you have left? A chain of cryptographically signed nodes that each point to their predecessor? That's been an underpinning of x.509 for, what, over 20 years? It's nothing new.
(I do agree that 99% of the decentralization of protocols can happen off the blockchain, amongst trusted parties... just saying that doesn’t get you all the way to “McDonalds Corp Replacement”.)