Perhaps so, it'll be interesting to see. As for my opinion of what caused culture to change, I think there's a nice way to reshape the question in an identical way. There's the interesting issue of how a middle class individual may state that they can't have kids right now because of the cost. Yet a lower class individual will happily do so and make things work, one way or the other.

Obviously the middle class individuals could afford to have children and make it work if they genuinely wanted to do so, but it might be uncomfortable and require some sacrifice. So it all comes down to priorities. So the question isn't why people stopped having children, but why priorities shifted so radically away from what is ultimately the most fundamentally important responsibility of humanity?

In the US from 1960-1980 many things happened. And one of these was a precipitous decline in fertility rates, plummeting by about 50% to where it would roughly stay to present day. It's quite unfortunate so many things happened in such a short time frame, because it enables one to create a reasonably compelling case for nearly any argument, including the common economic and educational (though those have many issues outside of this time frame).

One thing that also happened during that period was a dramatic decline in religiosity. And IMO that left a vacuum for meaning in society. And that vacuum seems to have been filled, for most, by indulgent hedonism that would gradually transition into consumerism. Drugs, the "sexual revolution", and various other issues skyrocketed during this period. This would further transition into the endless pursuit of the ever more expensive next shiny thing, be those Jordans, iThing, or exotic/expensive selfies for social media image crafting.

And what could be more antithetical to this shift in values and priorities than doing something that "might be uncomfortable and require some sacrifice"? There's certainly nothing more rewarding or fulfilling than raising a family, but that reward comes at immense cost and time.

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Ok, I wanted to hit more on how this hypothesis can also work as a casual explanation for the commonly observed correlations (education, income, etc) related to lower birth rates, but this post is already getting far longer than intended.