Just bad reading. Despite what you think this article says, it clearly acknowledges smart phones existed before 2007.

The source article is claiming 2002 as first availability, when Palm's and their ilk gained the ability to make phone calls.

Then it claims it took ~8 years to reach 10% saturation, and then another ~2 1/2 to reach 40% saturation.

I don't think you can call the first cell capable palm pilots the first smartphone, but that's where the article starts.