You're missing the fact that class mobility has changed wildly over time. Delaying having kids is class mobility play, trying to give your a leg up socioeconomi

You're missing the fact that class mobility has changed wildly over time. Delaying having kids is class mobility play, trying to give your a leg up socioeconomically based on your own heightened socioeconomic status. This was a VERY effective move during the 20th century, because the economy was in the biggest growth spurt in history. In contrast, you go back 150 years, and class mobility was for the cut-throated, extremely ambitious entrepreneurs. The idea of "get a better paying job working for someone else and fundamentally change my social standing" was laughable. Go back any much further than that, and socioeconomic class was basically immutable.