A close look at this situation shows that many of these overpopulated nations mostly in Africa and Asia are underdeveloped. While these underpopulated nations are economically buoyant. I think the reason for the poverty of these developing nations is not the population but bad governance and the inability to maximize and distribute available resources equally. We cannot deny the fact that these overpopulated nations are economically important to these developed nations in terms of human resources. And they contribute immensely to the development of these first-world nations in terms of cheap labour.
Mismanagement is also a problem, causing welfare to fall far short of what society expects. A country that has abundant natural products should be able to get out of the poverty line and be able to make people live at a much more prosperous and sufficient level, especially if human resources are not properly trained to process the natural products they have themselves. In the end they look for workers from outside to do what the people in the country should be able to do and the local people actually become unemployed.
They can take workers from outside if the number of workers in their own country has decreased because there are many people who bet their luck in other countries to make money now. I think this problem will never become a burden for these countries because they can take shortcuts to overcome the decreasing number of workers in their countries.