If you want to find root cause, you need to dissect that one number.

Without breaking out China vs non-China you would have concluded that Apple is slowing down/customers unhappy/products unattractive. This would have been the wrong conclusion for the non-China world.

You don't treat the world as one unified market.

Yeah, but "sales are down because the 2nd largest economy in the world is tanking" is very different from "sales are down across the board because people don't want to buy our products as much".

"Apple is rapidly losing business in china, but doing strongly everywhere else" is very different from "apple's entire business begins a slow decline."

Where does Apple "depends strongly" in China.

Sure is important for the iPhone, but it's not important for the iPad, Mac and Services.

Apple does not depend in any way on sales from China. Apple would continue to grow and prosper without any sales whatsoever in China, just at a slower rate/smaller scale.

People who constantly expect Apple’s rate of growth to continue at historic levels or even increase likely believe that Apple depends on sales in China to achieve this, and they are probably right. But nowhere in Apple being Apple is it mandated that they must continue their existing rate of growth. Indeed, as this quarter shows, that is impossible.