Wouldn't you want the word 'encryption' to be in the description, so there is no evil solicitor trying to argue about what 'secrets' meant. Or 'the right to confidentiality whenever, where-ever, and with whomever the person pleases'
But I would also not want the method of storage of secrets to become obsolete. The important thing is that I’m able to keep a secret, not how the secret is stored. For example, say quantum encryption comes to be known as “q-store” and is always said to be different from encryption. Now, what does that do to my rights if I move from traditional encryption to quantum algorithms?
Well it worked for copyright, we're kinda stuck with it, regardless of how much the we ways we store things have changed.