Haha, are you serious? One of the biggest demographic trends of the last century has been the rise of dual-income households, and we have decades of studies showing that the burdens are not evenly distributed.

Consider also that childcare isn’t a “ha, let’s ditch the kids and go clubbing” thing but a necessity for all but the richest households. Housing costs cause pressure both directly and indirectly: if you have to commute further to afford a house large enough for your family, childcare is essential to retaining the job which lets you afford that family.

I’d also note that I’m not saying the government should always provide everything but rather that to the extent that we decide birth rates falling is bad, we should assume that people are making economically rational decisions. There isn’t a simple nudge to shift a major life decision like this.