As the article says, bear in mind that a lot of those applications are now on iOS. They seem to think a shift to ARM might also mean a shift to iOS, with the iPad Pro acting as the bridge device to encourage software makers to provide compatibility (which seems to be working). One possibility might be Apple segmenting its laptop range, with the MacBook being shipped with iOS, and the MBP with OSX.

They say in the article that the entire PC market shipped fewer units than the iPhone alone, one quarter last year. There's certainly a risk that the consumer end of the laptop/desktop market gets dragged in behind as an 'additional device' for the mobile operating systems, bringing with it its walled gardens and concept of 'devices as utilities' rather than generic computing platforms.

I suspect as strange as it might seem to us a lot of people would jump on a laptop with the managed qualities of a utility device, especially if it meant they could get a Macbook for $150 less.