The blockchain works great for currency systems, and to an extent, smart contracts (provided they are not needlessly complex, or else you risk losing all stored funds to a bug/hack/unintentional loophole). Alas, there are not many other practical uses for the blockchain, owing to the fact that the very premise of the blockchain requires distributed nodes (which usually requires monetary incentive or a token), and it also requires the transparency of data. Now, it's very fun to think of big banks and companies using the blockchain for all of their transaction, but if this was implemented in the real world, the idea falls flat on its face. Why? Because no bank/company in their right mind would reveal all their information publicly, no bank/company in their right mind would let third (or even second) parties control their nodes. They would implement what is commonly known as a private blockchain. A private blockchain is also known as a database.