A masterful tour-de-force covering nearly everything important in the space. I particularly like your heavy indexing on Geruso (2023) fertility statistics, the strong support on income impacts by gender on fertility, the effect sizes of marriage and coupling, and the cuts by religion.
The only important part of the argument I think you left out is dependency ratios - the number of working adults per children or retired. I've found this line of argument useful particularly when talking to people aligned more towards the Left, because they want to provide welfare and SNAP and Medicare and Social Security, and ideally universal healthcare. But this is going to be exceedingly hard and cuts on all of these fronts are extremely likely, specifically due to our fertility gap.
You touched briefly on the demographic pyramid mismatch, but for America it's something very significant. Going by memory here, but it was ~2 workers per dependent in 1980, and it's ~1 worker per dependent now, and the ratio of "retirees" in the dependents is way higher now. By 2060, it's going to be ~0.5 workers per dependent, with a crazy amount of retirees, all using Medicare and SS - the math just doesn't work. And this is for the USA, which is much better off than most of Europe and East Asia, who will correspondingly have a much bigger problem.
Another thing I'd enjoy is a set of proposals for what you think might move the needle. You call out some things like WFH being a really strong effect, and male income, and lack of income while young with all fertility front-loaded there per Geruso, but have no policy or legislative proposals to move the needle on those.
Additional ideas on these fronts are intrinsically valuable - the fertility crisis is such a huge problem, and it affects so many countries in the world, that pretty much ANY idea that has a chance of moving the needle significantly while not taking away a bunch of rights from women is likely to be tried somewhere in the world in the coming decades.
Some of my own favorite ideas on this front:
1. Income tax - Federal income tax breaks for EITHER spouse for each additional biological kid, scaled so that if you have 6 kids, you pay zero income tax. It's a strong incentive to have more kids if either of you are high earners, including SAH mom plus high earning dad.
2. Brain trust bonuses - two STEM Masters holders get a $50k non-taxed bonus for each non-adoptive kid they have together. Two STEM Phd holders get $100k bonuses. Split the difference for a masters / Phd couple. Scale up or out as desired and as drives more incremental high human capital babies. Also extend it to those in the process of getting their Masters or Phd, because that’s them starting younger.
3. Child care - Greatly expanded and subsidized nanny / au pair programs in HCOL areas. You two are a "power couple" where you both make more than 6 figures, and have had at least 2 kids? Congrats! Have a free nanny / au pair!
4. Age gap relationships are the smart thing to do for both genders. I have a whole post on this (currently scheduled for two weeks from now) - the main concern is usually widowhood. Compton et al (2021) actually shows us that relatively long widow and widower-spans are the norm, and are the baseline expectation. "Even with minimal age gaps (~2 years), if you predecease your husband (.63 probability), "if she is the surviving spouse, her survivor life expectancy is 12.5 years. If the husband is the surviving spouse, his survivor life expectancy is 9.5 years."
This is just a simple function of survivorship and selection effects (ie the spouse that outlives is likelier to be healthier and longer-lived overall, regardless of gender).
In my upcoming post, I also argue that actuarially, the positive effects of selection and choosing known healthy men 10-20 years older more than offsets any prospective mortality gaps from choosing a same-age spouse.
5. One of the biggest problems is the mismatch between fertility windows and early career demands - but if we look at the larger picture of a human lifespan, there should BE no mismatch. Lifespans are long and getting longer, while fertility is fixed and front-loaded. And we could basically entirely fix this with a simple timing shift.
Given the male income things you also point to, we need a cultural norm where men speed run education to get a well-paying job sooner, and a dynamic where women marry younger and have some children while fully supported by that hubby, but while still planning on college / grad school themselves and shooting for beginning their own high powered careers around 35 when the kids are old enough.
One of the "carrots" for encouraging that scheme could be income tax reductions per-child that apply to the husband's income for the first ten years, then switches to the wife's income after that.
As a woman, if you start your career at 35 instead of 25, it should literally matter not at all - you have another ~50 years of life in expectation either way, and the ~30-40 years of effort put into careers before retiring fits neatly into either window.
Then we all get the best of both worlds! Nobody wastes their talents, but we still get a bunch of kids raised by talented, dual income parents. It's basically shifting "marriage and kids" from a capstone to a foundation, which is closer to what it was in the 60's - 80's.
A masterful tour-de-force covering nearly everything important in the space. I particularly like your heavy indexing on Geruso (2023) fertility statistics, the strong support on income impacts by gender on fertility, the effect sizes of marriage and coupling, and the cuts by religion.
The only important part of the argument I think you left out is dependency ratios - the number of working adults per children or retired. I've found this line of argument useful particularly when talking to people aligned more towards the Left, because they want to provide welfare and SNAP and Medicare and Social Security, and ideally universal healthcare. But this is going to be exceedingly hard and cuts on all of these fronts are extremely likely, specifically due to our fertility gap.
You touched briefly on the demographic pyramid mismatch, but for America it's something very significant. Going by memory here, but it was ~2 workers per dependent in 1980, and it's ~1 worker per dependent now, and the ratio of "retirees" in the dependents is way higher now. By 2060, it's going to be ~0.5 workers per dependent, with a crazy amount of retirees, all using Medicare and SS - the math just doesn't work. And this is for the USA, which is much better off than most of Europe and East Asia, who will correspondingly have a much bigger problem.
Another thing I'd enjoy is a set of proposals for what you think might move the needle. You call out some things like WFH being a really strong effect, and male income, and lack of income while young with all fertility front-loaded there per Geruso, but have no policy or legislative proposals to move the needle on those.
Additional ideas on these fronts are intrinsically valuable - the fertility crisis is such a huge problem, and it affects so many countries in the world, that pretty much ANY idea that has a chance of moving the needle significantly while not taking away a bunch of rights from women is likely to be tried somewhere in the world in the coming decades.
Some of my own favorite ideas on this front:
1. Income tax - Federal income tax breaks for EITHER spouse for each additional biological kid, scaled so that if you have 6 kids, you pay zero income tax. It's a strong incentive to have more kids if either of you are high earners, including SAH mom plus high earning dad.
2. Brain trust bonuses - two STEM Masters holders get a $50k non-taxed bonus for each non-adoptive kid they have together. Two STEM Phd holders get $100k bonuses. Split the difference for a masters / Phd couple. Scale up or out as desired and as drives more incremental high human capital babies. Also extend it to those in the process of getting their Masters or Phd, because that’s them starting younger.
3. Child care - Greatly expanded and subsidized nanny / au pair programs in HCOL areas. You two are a "power couple" where you both make more than 6 figures, and have had at least 2 kids? Congrats! Have a free nanny / au pair!
4. Age gap relationships are the smart thing to do for both genders. I have a whole post on this (currently scheduled for two weeks from now) - the main concern is usually widowhood. Compton et al (2021) actually shows us that relatively long widow and widower-spans are the norm, and are the baseline expectation. "Even with minimal age gaps (~2 years), if you predecease your husband (.63 probability), "if she is the surviving spouse, her survivor life expectancy is 12.5 years. If the husband is the surviving spouse, his survivor life expectancy is 9.5 years."
This is just a simple function of survivorship and selection effects (ie the spouse that outlives is likelier to be healthier and longer-lived overall, regardless of gender).
In my upcoming post, I also argue that actuarially, the positive effects of selection and choosing known healthy men 10-20 years older more than offsets any prospective mortality gaps from choosing a same-age spouse.
5. One of the biggest problems is the mismatch between fertility windows and early career demands - but if we look at the larger picture of a human lifespan, there should BE no mismatch. Lifespans are long and getting longer, while fertility is fixed and front-loaded. And we could basically entirely fix this with a simple timing shift.
Given the male income things you also point to, we need a cultural norm where men speed run education to get a well-paying job sooner, and a dynamic where women marry younger and have some children while fully supported by that hubby, but while still planning on college / grad school themselves and shooting for beginning their own high powered careers around 35 when the kids are old enough.
One of the "carrots" for encouraging that scheme could be income tax reductions per-child that apply to the husband's income for the first ten years, then switches to the wife's income after that.
As a woman, if you start your career at 35 instead of 25, it should literally matter not at all - you have another ~50 years of life in expectation either way, and the ~30-40 years of effort put into careers before retiring fits neatly into either window.
Then we all get the best of both worlds! Nobody wastes their talents, but we still get a bunch of kids raised by talented, dual income parents. It's basically shifting "marriage and kids" from a capstone to a foundation, which is closer to what it was in the 60's - 80's.