It doesn't, you could fit the entire planet in one city with the density of NYC into the state of Texas. Overpopulation is a myth perpetrated by the ruling elite as an excuse to get you to accept their mass human culling through slow-kill methods they are doing right now in front of your face with the food, water, air and medicine.

The real issue is the technologies they suppress that would create an excess of energy, which is the driving force for industrial advancement and lifting people out of a state of poverty.