I think the point is that Sillicon Valley is huge, and this is where people to go build their ideas.
You talk about Germans, French, Chinese etc, but reality is that a lot of people around the world who have an idea they really think will make it big will actually move to Silicon Valley to make it happen.
Because that is where the connections and the funding is. You can read about Skype to see how tricky this can be in Europe. Some Swedes had an idea, but they utilized software developers in the Baltics to build it, but got funding in London, because neither Sweden nor the Baltics had that kind of VC funding scene.
Basically what it took 3 different countries in Europe to achieve can be done in one single location in the US.
What this article was trying to explain is what while Silicon Valley is where it all happens, one also has to keep in mind that it is an American bubble.
Sure you could make pedantic points about the inhabitants of Nuuk on Greenland was too ignorant to build this app, but such an argument makes no sense because Nuuk is not known to be spitting out tons of apps, or having a vast amounts of developers, VCs and visionaries.
So singling out Silicon Valley made totally sense here. I tied in specificically with the arch of the story.