There was a speculative bubble in the world real estate market. This led to a lot of real cash circulating (e.g. people refinancing to pay for kitchen remodels so that they can flip their home). That popped, and all the excess economic activity disappeared with it.
The article posits a broad trend. Short term boom and bust fluctuations will always happen.
The article posits a broad trend for which it provides no evidence, and indeed nobody has been able to provide evidence. This is the broad trend people have been positing since the ludites were smashing those newfangled automated looms.
The article posits a broad trend. Short term boom and bust fluctuations will always happen.