You’re talking about data stored in the apple cloud (I think without the account recovery turned off, but I’m not 100% on that). The same is true of googles cloud services.
Agencies haven’t been focusing on getting the actual texts that say “here I go, doing something you don’t like!” For quite a while because of the amount of variability involved. What I hear spooks talking about is building enough pc for a rubber hose interrogation with unsecured parallel data streams like push notifications.