I think it should be noted that even with with encrypted data you'll generally just encrypt the master key with multiple passphrases; one (or more) master keys

I think it should be noted that even with with encrypted data you'll generally just encrypt the master key with multiple passphrases; one (or more) master keys for admin use and one for the user themselves. There's really very rarely a good reason to share any secrets. It's pretty much a necessity for any larger business that device data be protected with the user's own password and with a master password known to IT so that it can be accessed when the user's password is inevitably lost.