That’s not how it typically works though. Your car has to be tested regularly, at least in Europe. Your bag is searched when you travel, in an infinitely more intrusive way.

Also , your photos are only scanned on their way to iCloud. Turn off icloud photos and nothing will be scanned.

Besides, the laws around child porn have always been different from other laws, they have preemptively scanned for that for as long as I can remember, without probable cause.