Point taken. Here is the problem with this argument: labor isn’t the only input to productive capacity, and China’s population is far passed the point where labor is the bottleneck. If China can’t get enough oil, gas and other resources to fuel its industry and feed its people, it won’t matter how many workers it has.
As far as I can tell, we can settle this entire debate with one concrete question: of all the consumer goods China’s/Your/My population(s) are buying, what percent of their value is due to the basic inputs like rented land and minerals, and what percent of their value is due to labor? Then apply your laffer curve and we will be able to calculate exaclty when new people “should” reduce per capita income statistics.
As far as I can tell, we can settle this entire debate with one concrete question: of all the consumer goods China’s/Your/My population(s) are buying, what percent of their value is due to the basic inputs like rented land and minerals, and what percent of their value is due to labor? Then apply your laffer curve and we will be able to calculate exaclty when new people “should” reduce per capita income statistics.