OK. I'll explain. SHA-256 is used for hashing. Of coz it's used in a variety of applications. But if someone get a quantum computer and manage to falsify a digitally signed contract then only authentic owner of the contract will be harmed. If someone manage to falsify an SSL certificate then only visitors of the site will be harmed. But if someone manage to find block nonces every second, then everyone who uses bitcoins will be in troubles.