What kind of worries me, is when I shifted to Apple, I was certain that Apple was more committed to the OS X ecosystem than Microsoft was committed to the Windows ecosystem.
This was in the era of...
"Here's Windows ME and Windows Vista. It's slower than the last release, a hell of a lot less reliable, will attract more viruses than Charlie Sheen, will crash your programs that ran fine on your previous OS, won't work well with your older devices, won't work well with new devices, and frankly we don't give a poop, because Bill Gates is swimming in an olympic sized swimming pool filled with the cash (and tears) that this horrible software has generated. And if you have a problem, feel free to call someone else, because we don't care."
At the same time, Apple was like...
"Here's OS X Snow Leopard. It has NO NEW FEATURES, but you are going to love this because, unlike Windows, it works right the first time around, it's logically designed, it's fast as hell, it works great on older and new machines, and it sure is reliable. And yes, the Server version works great too."
Today, I don't have quite such certain feelings regarding Apple's commitment to OS X...where as El Capitan said to me they are still strongly committed, something like the formally endorsed LG 5k monitor debacle and graphics glitches with Sierra said the opposite. That would be fine if I still felt the same way about Microsoft, but I don't. Microsoft realized that Windows, despite the larger sales, was always seen as an inferior version of OS X. Their commitment to Windows 10 seems to be tremendous, and their customer service IMO has gotten almost as good as Apple.
So I'm uncertain what the future will bring. I wish Mr. Cook the best, and I hope he delivers on his commitments, and I hope Apple as a whole realizes the importance of delivering, since Microsoft is clearly gunning for many of their long-term Users.