I'd point to the biggest change being the destruction of extended family living in developed countries, and consequently shifting child care costs directly onto

I'd point to the biggest change being the destruction of extended family living in developed countries, and consequently shifting child care costs directly onto working age parents. Historically, countries got it both ways: - Working age parents contributed the bulk of their time to the economy (historically: male, more recently: both) - Older family members, especially grandparents, contributed free child care Now, geographic mobility and preference have decreased the rate at which grandparents are co-located and available. And, critically, having children later in life has decreased the number of years grandparents are able to help. If governments provided a net-zero cost, high-quality option for childcare, I feel like it'd substantially change potential family decisions. But that's one of the substantially-more-expensive-than-current-benefits options you're talking about.