But SSN should not really intended to be secret. It is not designed to be a proof of identity, but so many companies have treated it that way that it gives more

But SSN should not really intended to be secret. It is not designed to be a proof of identity, but so many companies have treated it that way that it gives more access than it should. If we could prevent companies from using it like a password, it would no longer be a major risk to have it exposed.