The population is greatly overcounted. How do sub Saharan countries get enough money set aside to do a census on their populations? Same goes for India and China. The logistics are insane. It takes America over a year to fully count the population. And we use proven methods to speed it up.

But its not about population. It's about farming space. And we can easily produce enough cultivated acreage to feed Humanity forever no matter the population. Not to mention aquaculture and modern methods.