The birther culture in Hawaii is absolutely disgusting : TwoXChromosomes

Good question, I think it's the result of the panic in the 80s that they began teaching that having a kid while young would ruin their lives forever and how awful it was to be a parent. I assume some form of this spread to other nations per the efforts of the WHO.

Unfortunately it worked too well. We can't even be replaced by immigrants because they stopped having kids, too.

You could reverse course and show why having kids is desirable (fulfillment, happiness, social responsibility) and offer Singapore like incentives. I think they pay 25k for a kid.

I honestly think fighting atomization is the key. At least in the US, too many people withdraw from life.

Other countries have tried direct payments to parents: Russia began offering a one-time sum of about $7,000 to families with more than two kids, while Italy and Greece have experimented with per-child “baby bonuses.” In 2019, Hungary introduced a loan of around $30,000 to newlyweds. If they have three children, the loan is forgiven.

Public-education campaigns have also emerged, essentially begging people to reproduce. In Copenhagen, for example, a 2015 poster asked, “Have you counted your eggs today?” In 2012, the Singaporean government partnered with Mentos to release a rap video encouraging couples to “make Singapore's birth rate spike.” (“Only financially secure adults in stable, committed, long-term relationships should participate,” the campaign clarified.)

So far, most countries have tried either asking people nicely to reproduce or sweetening the deal with money. If that doesn't work, however, restricting people's reproductive choices may be on the table, especially in more autocratic regimes. In Iran, where the government in the 1990s made birth control cheap or free in an effort to curb population growth, authorities are now cracking down on abortion and contraception as part of a drive to boost births.

Regardless, it will probably work out okay by attacking the other end of the population cycle, they're already trialing drugs to target senescence. Automation will also require less human labor, so we might all be fewer in number and sharing a bigger pie. It might end up being a smaller, very wealthy population, as opposed to the /r/collapse prediction of climate refugees and living in a pod. Society is going to change more, though, and those of us who end up here for an extended stay might get some culture shock.

This would be true if the decline seemed to be temporary but it really just looks like people are eschewing family life entirely. You could explain a ten year dip as the result of a generation choosing not to have kids until later, but fertility rates have been in decline for decades.

Only so long you can wait before it stops being possible.