I see you're among the group I was referring to which feels that the entire human race dying out or descending into stone-age collapse is a W as long as 'carbon number go down.'
There is absolutely no reason we need to continue increasing the human population when we clearly have trouble using and allocating the limited resources we have now. Doesn't concern me one bit if birthrates are falling. I might start to look into it if population falls below a couple billion, which it was for all but the last 100 years. But population is project to continue rising until 2084 anyway, which means I don't need to think about this problem at all for the remainder of my life.
> clearly have trouble using and allocating the limited resources we have now
> But population is project to continue rising until 2084 anyway, which means I don't need to think about this problem at all for the remainder of my life.
Your first point sounds like you are probably the kind of responsible person who is pretty concerned about climate, emissions, wealth inequality, etc. Which implies that you consider it a duty to not just do whatever is convenient in the now, but to act in a sustainable way that doesn't screw future generations.
Then you drop that second bomb, which implies maybe you don't give a crap if today's teenagers will inhabit a horrific world with twice as many old people as society can afford to support. You'll be gone after all, so you "don't need to think about it." If you are that callous to the plight of generations that come after you, I guess you have more in common than you think with those people who are supposedly doing such a bad job with the "resources we have now."
Sure, it's hard to imagine any solution where someone doesn't get screwed, but I think I'd rather be screwed by underpopulation than over population. I just happen to live in the timeline which I think is much closer to overpopulation. Alas, I consider my opinion to be much less valuable in such a world with so many more voices.
I dare say I think I have plenty in common with those other people, as I do care a little, but maybe not as much as I could or should. I think this is how we got to this point in the first place.
> maybe you don't give a crap if today's teenagers will inhabit a horrific world with twice as many old people as society can afford to support
I wouldn't say that a lower population needs to result in a horrific world.
I assume standards of living would change. What other choice is there, given the change in the ratio of workers to retirees? Not everyone could afford a big house of their own, a car, and tech toys and other possessions, but we are productive enough as a society to feed, cloth and shelter everyone, including a bunch of retired people. We could still afford the really important benifits of modernity. And we keep getting more productive, finding easier ways to do more, so who knows?
The Ahmish wouldn't describe a simplier way of life as as horrific. Nor people born a hundred years ago. Nor people living like that in many countries today. Change society like that and, who knows, young people might be more open to having kids again.
Why do you think things would end up being horrific?
The Amish have tons of kids and are one of the fastest growing groups you could think of. It's because of this high birth rate that they're easily able to care for their elders, even though they are IIRC legally allowed to opt out of Social Security.
Having a very inverted population pyramid, where the old vastly outnumber the working age, and the working age outnumber the children, isn't something that would be a minor inconvenience. Our economic system will collapse because it takes a lot of people creating value to pay for the needs of the elderly (remember, there isn't some big trust fund set aside for them -- it's only through the wages of the currently-working that we can pay the benefits for them, and if I'm not mistaken, public pensions in other Western countries are exactly the same in that way). And setting aside the money abstraction, which is just how we organize things, the elderly need a lot of medical care and they consume food, water, need housing to live in, and they can't contribute much to the work of making those things. So they need there to be enough younger, working people that there's a big surplus of stuff not needed to keep the young fed, clothed, and housed, and a surplus of young people to work to take care of them.
I'm not one who insists on some unsustainable growth or even any growth at all. A 0 growth rate would be fine. But the nihilism in the West (coupled with too many economic incentives to not have kids) that has killed off our birthrate is going to make the decline in living standards that's been seen between the boomers and our generation (you know, all those think pieces about the "Death of the American Dream") look like a joke. And economic collapse doesn't mean we just shift to living like the Amish. It looks more like Haiti.
So does that mean our social/political/economic system (culture) is a failure - having created the conditions for population decline (including industrialization and urbanization), but unable to survive the consequences (shrinking birthrates)?
Lots of the world gets by on a fraction of US per-capita GDP, and isn't as screwed up as Haiti. Countries like Japan, Korea, Italy and others in Europe are blazing trails with this problem, a generation of aging (no millenials) ahead of the US (assuming no more immigration). We'll see how that works out.
Scary to back-slide on standards of living, but it's happened before in history. Best not to get too comfortable with the idea of the American Dream. Stay flexible. Stay healthy. Good luck!