Privacy and security seem orthogonal to me.

Privacy is only one thing of many that could be assured via security. Imagine an office with glass walls, very little sound insulation, and a security guard at the door. The security guard and walls prevent physical attacks on the office occupant, thus ensuring their physical security, but it'd be difficult to say that office is private.

Is iPhone private? Apple says it is. Yet Apple also has the keys to user iCloud data. I agree that with proper metaphor the distinction becomes very clear, but in the open I’m not so sure if this distinction is well-defined, well-used, or well-understood.