When I moved to Manhattan, I was shocked to see how many apartment buildings that are only a couple floors tall and don't have elevators. I assumed every building in Midtown would be at least 50 floors and house thousands of people.

Counting the office space, which is completely unnecessary when people can work from home, even the densest neighborhood of America's most populated city has tons of room. I would bet that we can fit 20 times more people in Manhattan if we got rid of the height limitation laws and converted all the offices to apartments.

On the other hand, when we consider the average suburb there is a ridiculous surplus of land. We could fit the entire world population into Texas if we used it more efficiently.