To translate it to a more common sentiment: "we'd like to have kids, but don't feel stable enough" or "we would have kids, but can't afford a house"

Seems very false to me. The rule, for hundreds of thousands of years, has always been to have kids whatever the situation, despite much higher risks and adversity in general.

Even today, the people still making kids are largely those in the poorest deciles of the population, with no stable home, etc.

Women were not quite in control of becoming pregnant until very recently.