> The market forces are the entire realm of what’s possible, now and in the future.

I actually suspected as much and left "competing smartphones" somewhat vague.

> When Windows seemed entrenched forever

It's still entrenched! Microsoft got a slap on the wrist by the government right before September 11, and antitrust enforcement has been on a holiday ever since.

> the platforms that eventually surpassed weren’t the competing desktop OSes (Mac and Linux)

In terms of revenue, desktop computers were surpassed by smartphones, but they were not replaced by smartphones. I don't consider them to be directly competing products, and most of us who can afford it own both. A smartphone fits in your pocket, whereas a keyboard and pointing device and large screen will never fit in your pocket.