Pickpocketing is quick and easy, sometimes not even a crime, and even though phones are locked, you can sell the Android phone for pieces. That's not the case for the iphone.
In many places, it's a crime according to the law, but if nothing happens with thieves or reported theft, then in terms of consequences it's not a crime.
I think you're using a different defintion of "crime" than I am (unlawful activity is probably the simplest). "Unenforced" would be probably a better term. e.g. Speeding in a car is a crime in a lot of places, but is often unenforced.
You can definitely re-use or sell iPhone parts. Most of replacement parts shops have access to are not sold directly by Apple.
As mentioned in the article, some parts won't work and others will show warnings. And sometimes you can reprogram chips with small devices easily available from China, which essentially defeats Apple's hardware pairing.
I find that difficult to believe.