Smaller population is easier to control, that graphic is not doing justice to what is actually predicted to happen.

The world population flattens out as people get out of poverty, third world countries have many children and many die before their 5th birthday.

If you have ever flown over the country or like me flown over Australia you will see endless land and untouched natural environments. The actual urban area takes up such a small part of most countries, really our impact is tiny in the grand scale of our world.