Population shrinkage, sustainability and the mother of all parties

This is from the Science news item The upside of downsizing:

“Humanity is already consuming resources at an unsustainable rate; population shrinkage is the cheapest and surest contribution to sustainability that we know of,” says Simon Ross, chief executive of Population Matters, a London-based group pushing to restrain population growth to reduce stresses on the environment.

Indeed. If we decided to have no more children, those alive could then set to enjoy consumption without worries about sustainability.