I honestly don't get the uproar here. This is opt-in, so how is it any more outrageous than existing MDM software that people opt-in to for work reasons which are way more invasive?
If it's opt-in it's entirely useless for its stated goal, because why would the bad guys choose to subject themselves to such scrutiny???!?
So the very fact that it is opt-in means it doesn't even try to "protect the children"; it just uses the children argument to promote the idea of total control, which will be then used for a host of other purposes.
It's not opt in. Please do more reading on it. Because of a technical "limit" currently you can turn off icloud photos and get out of the worst of it but then you also handicap your device and one of the reasons people buy into the apple platform in the first place.
