'All our problems would be solved if the world's population were reduced by 90%'...

'All our problems would be solved if the world's population were reduced by 90%'.. This statement was made by the British Ambassador of Peace to the UN Jane Goodall: 'We cannot hide from the growth of the human population, because you know that this is at the root of all problems. None of this would have happened if the population was like 500 years ago'...

Why do such people (promoting population reduction) not even think to start with themselves?