I don't think there is survivorship bias here. If you simply track the percentage of people having children over their lifetime you can build stats like this as a type of ground truth in relation to census data etc.
The issue is in the interpretation. Your sampling is biased so the immediate conclusion is false. If you want kids and are over 30, your chances are better than 50%.
The society that figures out how to properly overlap child rearing in an educational environment will survive. I’m fascinated with how much the world is going to change in the next century with most of the world set to shrink and be dominated by the elderly.
I see more of the population in the US going the way of Asian cultures (I am first generation Indian) where you have multi generational house holds being more common. It is going to be a painful cultural shift, especially for the highly individualistic American culture - but that is the only way I see future generations surviving.