[phil21]

Let those places grow feral again. We don't need to take up the entire damn planet as a species. Or at least the entire "fertile" bits of it.

I could not be more diametrically opposed to your position. It's clear to me we have far too many people as it is, and the only way out is through population decline. Anything else is ridiculous line noise to argue about. Once you solve the CO2 climate change problem you have about 10 other just-as-bad crises right behind it if population growth continues.

Sure, as you say there could be some more black swan events in science/technology that technically lets us expand in the short term much like modern agriculture has. I don't see that as a positive as it simply delays the inevitable and makes it even more impossible to recover from.

[alf-pogz]

I suppose it's a matter of how much you appreciate human achievement. Detroit could become the realization of a new Metropolis. Hyperloop could be built between Detroit and Cleveland and other cities with much less regulatory constraint. The promise of these mid-western cities excites me much more than the west coast because we do not need to be bogged down by preservation of natural landscapes there. They are the areas that could have delivered millennials from their stagnation if momentum had taken hold.

There is no choice but to grow. People like to travel, conduct scientific research, and face and conquer new technical challenges. You cannot do this without more people and the productivity they provide. Period.