As a daily CarPlay user it lets me access Maps, calls, read\respond to messages via Siri, access locations to navigate to from the calendar and play Music or various radio streaming apps...think thats more than plenty to play with whilst also trying to drive a car!!
For what its worth Android Auto doesnt do much more, as standard it only allows access to navigation apps, phone calls, messaging via voice recognition and music\audio streaming apps just like CarPlay. Probably easier to fool it to allow access to other stuff but doesnt mean its right they are used. I cant see the cops accepting that it was ok to be speeding because you were watching the latest iPhone unboxing video via Youtube!