Randy, this is spot on:
A number of years back Apple pulled back from most of their high-end products. They realized that their software mostly only existed to sell their hardware.
What too many folks who complain about Apple software don't realize is that Apple is, at the base, a hardware company. They give away the OS, give away the Works suite, just to make the hardware reasonably attractive. MicroSoft is, at base, a software company who sells an OS, sells an office suite, but who manufacture a small niche of hardware on the side (tablets) to sell more of the software.
So Apple, by moving to all ARM CPUs in all devices, is going to merge the OS for all so that that environment of hardware is more attractive. Imagine the unification of Mac and iDevices to the point where a task can be launched on an Watch, seamlessly moved to an iPad, then finalized on a Mac and send back down to the Watch and iDevice, all with no real change in functionality other than the input mechanism (keys, taps) and the size of the output. Apple is coming close to that with their various health offerings. I can wear my Watch while I work out, record the workout, along with heart rates, distances, effort, then with zero interaction on my part, that same data is available on my iDevice (iPhone and iPad) in the health app. The next step is to have that exact same app run on my Mac so that it, too, gets the inputs from my Watch. Now think about that link in security applications. I already unlock my MBP with my Watch, authorize software installations with a double click on the Watch, and pay for items with Apple Pay or cards in my Wallet with taps on the Watch. Integration is coming, and will arrive much sooner with all ARM devices in the stable.
What that integration means is that if you buy any one of those devices, the other will immediately be more attractive to you, hence Apple sells more hardware and maybe more services to support that hardware.