This has happened to every single society [*] as it industrializes [0], and offering extensive support and incentives to parents (e.g. as has been tried in Scandinavian countries) does very little to reverse this trend [1, 2].
My hypothesis is that as societies industrialize, they afford their population more and more activities that are simply more fun and rewarding than having children. So many people I know put off having children (or curtailed the number they had) because they were reluctant to give up the activities only available in a childfree/one-and-done life. Ultimately, we are hedonistic creatures, and having kids is antithetical to the myriad hedonic pursuits available in wealthy, industrialized societies.
[*] Israel is the lone exception, due to its Orthodox Jewish population.
My hypothesis is that as societies industrialize, they afford their population more and more activities that are simply more fun and rewarding than having children. So many people I know put off having children (or curtailed the number they had) because they were reluctant to give up the activities only available in a childfree/one-and-done life. Ultimately, we are hedonistic creatures, and having kids is antithetical to the myriad hedonic pursuits available in wealthy, industrialized societies.
[*] Israel is the lone exception, due to its Orthodox Jewish population.
[0] https://ourworldindata.org/global-decline-fertility-rate
[1] https://pub.nordregio.org/r-2024-13-state-of-the-nordic-regi...
[2] https://pmc.ncbi.nlm.nih.gov/articles/PMC10049131/