They are making money hand over fist, and given the profits apple is enjoying, Cook won't be going anywhere BUT and its a big but. Aside from the phone, their business has not been stellar. The iPad is cratering, its been sliding for 13 quarters, the mac business has bounced back a bit but nothing really exciting. Apple is enjoying its profits from the iPhone that has not markedly change in years. We get emojis and a thinner product, while the competition (whether phone or PC) are pushing the envelope.
While I don't think apple is doomed, I don't see a clear focused strategy.