This is a non-solution. Its basically saying, why don't we just go back to living like before we had technology. That is not gone happen because people want do those things and consume those things. And people already have made those decisions.

The people who were predicting doom because of population were utterly and completely wrong and have been for 50+ years now. Just as terrible a prediction as those who predicted 'Peak Coal' in 1870. Guys like Borlaug are good at what they do but their understanding of the economy is incredibly limited.

The idea that population was the big issue is just fundamentally flawed assumption. The idea that population growth needs to end in order not to have a huge catastrophe is also incredibly flawed.

And add to all that, we can have both population and consumption growth at the same time, and we had that for a long time now and we can continue to do it for a long time. The energy inherent in the LITERAL DIRT on the ground alone could power advanced human civilization for 1000s of years and that is before we even start considering space based resources.

Simply put, with the 3x3x3 Cube of Dirt from where you are now, you have enough Thorium to literally power your whole life, including flying around with airplanes, driving and so on.

In fact we can do that AND at the same time reduce the amount of space people actually life on. Forest and other nature preserves are growing in the Western world. Increasingly people will live in population centers and more and more of the land around will have little actual use other then looking at it.