Provable how? iOS software is closed source and unverifiable. New code can be added to send any data anywhere at any point. Explain to me how you prove closed source software won’t send data under its control ever.
And we don’t even need to go as far as key exchanges, and forget about Find My. Maybe those are better protected and it’s harder for them to pull a sneaky without someone noticing. The location data of your phone isn’t in Secure Enclave and the OS can do whatever the hell it likes with it, good luck verifying a huge closed source OS which phones home all the time isn’t sending your location home. At the end of the day you’re trusting them (or just don’t care because you probably aren’t pissing off TLA, which is certainly true in my case), provable security is extremely limited.
And we don’t even need to go as far as key exchanges, and forget about Find My. Maybe those are better protected and it’s harder for them to pull a sneaky without someone noticing. The location data of your phone isn’t in Secure Enclave and the OS can do whatever the hell it likes with it, good luck verifying a huge closed source OS which phones home all the time isn’t sending your location home. At the end of the day you’re trusting them (or just don’t care because you probably aren’t pissing off TLA, which is certainly true in my case), provable security is extremely limited.