Apple uses end-to-end encryption for iMessage, which is the only Apple-related confidential communication I can think of (well I have no idea what the guarantees around FaceTime are).
Uhm, Apple also holds emails, calendars, contacts and notes on their servers via iCloud.
Notes can be set as secure, which encrypts them with a password Apple doesn't have access to.
Beyond explicitly using secure notes (which are encrypted), I don't recall Apple promising "confidentiality" of those things. I mean, I don't expect Apple to give that data to others, but I also don't assume Apple has no way of accessing that given a court order.