There's not much more to say about The Economist article other than it is funny and interesting to see how the Russian GDP is equivalent to the economy of Texas, or how the California GDP is equivalent to Italy's. Funny and good for a tweet or for a Facebook share, that is all.
They have not included fundamental data about level of education, per capita productivity, access to health, GDP per capita, and a long list of variables that must be taken into account when comparing countries or regions in a more meaningful way.
Another interesting exercise would be to compare China's GDP with the rest of the world, and see the evolution of that comparison over the last 20 years.
It has long been true that California on its own would rank as one of the biggest economies of the world. These days, it would rank eighth, falling between Italy and Brazil on a nominal exchange-rate basis. But how do other American states compare with other countries? Taking the nearest equivalent country from 2009 data reveals some surprises. Who would have thought that, despite years of auto-industry hardship, the economy of Michigan is still the same size as Taiwan's?
Image from www.economist.com