Developed countries have dwindling population (well, at least exclusing immigration). And I think it's safe to assume when other countries catch up similar thing will happen, at the very least to the point of levelling up. Hell even India, the biggest country by number of people, is already at 2.0

We don't need to feed more, we just need to bring the education and standard of living if the world up. And maybe figure out how to make the people in developed countries to have sustainable birth rate...