How can a smart, presumably educated person not know that rent counts as economic activity?
To say the world is poorer than in 2008 is just utterly preposterous.
Per capita GPD in China went from 3500 to 12500. India 1000 to 2200.
There is half the world. US, Canada and Europe is only 15% of the population but I don't know how the case can be made we are poorer than in 2008 either.