The optimum human population of earth is zero

The optimum population is, then, less than the maximum.

If I were reincarnated, I would wish to be returned to Earth as a killer virus to lower human population levels.

That's a population that has obviously decided to live there, but still, most have to come into the city to work or go to school. Most of those people who live in those areas like to get where they want to go . . . without stopping 50 times between when you get on and off.

Of course, a positive growth rate might be taken as evidence that a population is below its optimum.

The beach population has been light during the week. Plus, we have had flat water. But that is all subject to change.