The general case is: federation of individuals can compete with single large corporation because cryptocontracts provide equivalent operational stability to what a single controlling entity can provide.
When corporate bylaws are written in code, you can replace a single legal entity with thousands of former employees operating as sole proprietorships.
Sure, but you don't need proof-of-work for that. All you need is for every participant to ratify the bylaws-as-code, which you can do with simple public/private signing. The only reason that proof-of-work is needed for a currency is that the ledger is changing constantly. For something that changes infrequently, the double-spend problem (or the contractual equivalent) isn't nearly as big of a deal.
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.
How do you verify the ratifications without a blockchain? You’d need to meet in person ahead of time right?
(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”.)
When corporate bylaws are written in code, you can replace a single legal entity with thousands of former employees operating as sole proprietorships.