I think you pretty much have it.
One thing: This update-teach-update process is not new. This has pretty much been Apple since Jobs came back. Late 90s and forward they have changed items and tried to teach people about them slowly. Software yes, but hardware and style too - generation building on the last.
The difference now seems to be $$$. With so many new users they are making bigger changes each generation whereas the traditional approach as you grow is to make smaller changes. The more money you earn the more conservative and slow the company becomes to protect investment. I love that Apple is ignoring that method entirely.
Also, full screen apps are old, not new.