We have to look at it from the population density perspective. If China and India suddenly break apart and form smaller independent nations, are they still overpopulated? Let’s compare China to a skyscraper. 1.4 billion people live in China’s skyscraper, but it has many many floors to house them all. Meanwhile other countries may have smaller populations, but they also have a smaller land area. China ranks 59th in terms of population density. Still above average, but lower than Japan, South Korea, Taiwan and almost all of western Europe. It’s still above average, though it would be unfair to call China or India to depopulate, when many countries are more densely populated (at least compared to China).