Even Elon Musk knows that population predictions are long term things. The people who will be having children in 2050 are largely already alive today. And the people who will be – at the end of their naturals – dying then are also all alive today. Thus how many people there will be in 2050 is largely baked into the number of people who are here now.
The thing that will make a difference is the combination of falling fertility rates and the extent of the demographic shift. And Musk’s likely to be right here in the direction of his disagreement with the United Nations predictions:
ELON MUSK: CIVILIZATION COULD COLLAPSE IN 30 YEARS
No, that’s not what he says at all, don’t be silly.
What Musk did say:
Real issue will an aging & declining world population by 2050, *not* overpopulation. Randers estimate far more accurate than UN imo: https://t.co/cdHf62bxpb
— Elon Musk (@elonmusk) June 21, 2019
Something that’s a great deal less controversial. The UN predictions have, for decades now, overstated population growth. For they’ve underestimated the fall in fertility rates – the number of children people have. The reason they’ve done so is that they’ve failed to correctly estimate two things. Firstly, how fast economic growth in the poor places of the world will be, then how much people will respond to that growth by having fewer children.
It’s true that the Randers estimate is a little outside the UN projections. But it’s not that far outside the “low” version of that UN prediction. The 9.6 billion is the UN’s middle one.
And historically the actual outcome has been, for some decades now, somewhat below the UN’s low projection.
Oh, and, well, the prediction isn’t of civilisational collapse. It’s of the world getting rich. It’s that the poor get richer so they start having fewer children like rich people do. And somehow the world getting rich just isn’t consistent with civilisational collapse now, is it?