You’re saying that technology has solved the overpopulation issue every time – and I actually agree with that.
But you’re also saying that population decline is going to be catastrophic – why are you assuming that technology will be unable to solve that problem?
Good question. They are fundamentally different problems. Some argue that technology could solve that issue as well and some people believe that indefinitely increasing lifespans will hold populations steady even as TFR continues to stay below 2. In the medium term, that could even be true since total population won’t actually start to fall until death rates exceed birth rates. If one extends lifespans, one pushes the date of that occurrence further back. But even that doesn’t fundamentally solve the problem, it just changes the time scale. We’ve never in history seen life extending technology significantly move back the date of menopause. So there is no reason to expect that longer lifespans will lead to more children unless that happens. And since medical science has already determined that women are born with all the eggs they will ever have, this seems unlikely. On the contrary, a longer lifespan will lead to an economy where higher education has a bigger payoff than dying at 70 did (more years to recover the investment). There has always been an inverse relationship between women’s educational level and number of kids they have (population level here, no anecdotes folks!). Nobody has solved this conundrum yet.
So short of technology allowing cloning of human adults (shudder), there is no incentive for technology to help populations recover. On the contrary, the modern, wealthy technological society presses people to have FEWER children, not more. I’m not able to see how that changes. Yes, SOCIETY will develop a drastic shortage and need for young people. But modern economics innately rewards the individual who does NOT have children over the one who does. I can’t see how technology can make the situation better. If anything, it makes the problem worse.
On the resource improvement side, technological development rewards both the individual who innovates and the society at large which increases its total resources so that larger population can be supported. Both win. See how different that is?
Some might suggest that technology will eventually give us artificial wombs that will relieve women of the discomfort and inconvenience of pregnancy. I predict that will backfire and result in FEWER people having children, not more. Same reason free condoms lead to more STD and unwed mothers: failure to comprehend the nature of things and the effects of uncoupling our actions from our natures.