One random app (Facebook in my example) can NOT access another random app's (sms in this case) data on an iPhone where it can (or could before the very current

One random app (Facebook in my example) can NOT access another random app's (sms in this case) data on an iPhone where it can (or could before the very current version) on Android. You might call that "Freedom" and "not a walled garden", I call that cross access to data a nightmare and am happy that it is a none issue on IOS. YMMV