20 Billion? They must be joking!
I have recently been reading various reports expressing concern about the world population reaching 8 or 9 billion, and the problems which will arise because of food, energy and water resources.
An example: I live on an island with a population (probably) of less than I million. As recently as a few months ago our reservoirs were (well) below 10% capacity. We had mains water about 33% of the time, other parts of the island were not so lucky. We have had an unusually 'wet' winter, so we're up to about 20% capacity and mains water most days. But we have to build another desalination plant, which runs on (oil-powered) electricity.
And this is a (theoretically at least) 'first world' country and part of the EU.
I accept, of course, that in the 'fantasyland' that is JW doctrine everything may be perfect. But (as always) selectively (and corruptly, IMHO) quoting scientific or pseudo-scientific stuff to try and predict and support their fantasies is dishonest.
Better they just say 'the paradise fairy will ensure everything will be wonderful'. And you know what? I doubt that many convinced, or scared, or brainwashed, or apathetic dubs would challenge them.