This is actually happening with Millennials. Strauss and Howe predicted a "Crisis of 2020" that would lead to civic renewal and presumably a higher birth rate, but it now appears that 2020 was the beginning of the crisis and it won't be resolved for some time, perhaps a generation, and by that time Millennials (globally, the last big generation) will have aged out of childbearing years. Any baby boom will be led by late Zoomers, at best, and that's a small generation that's already affected by the collapse in birth rates.
My takeaway: the globalized, technologically advanced society we have now is doomed to collapse, and we should be working hard to take that advanced technology and identify simplified versions of it that can be run and maintained by a much smaller, localized workforce.
One thing that makes me suspect the population crash will be much harder to fix than the previous population explosion, it's that there's no immediate fix. It takes ~20-30 years to raise a human being into a fully functional member of modern society, after the decision to conceive them was made. It's a long term investment. Back when people panicked on population explosion, some of the proposed "fixes" were brutal, like forced sterilization in India[1], of Forced abortions in China[2], but they could be implemented or stopped quickly.
There's fundamental asymmetry. Time to terminate an unborn child is measured in hours to days (counting the recover time for the mother). Time to fully _raise_ a child is measured in decades. By the time people panic over it, it may be too late to avert the crisis.
[1] https://www.aljazeera.com/features/2025/6/25/india-forcibly-...
[2] https://www.npr.org/2016/02/01/465124337/how-chinas-one-chil...