It’s this everywhere: the constant fear of not raising children perfectly in every aspect puts downward pressure on a family’s desire (and perceived ability) to have more children.

I don't think it is about raising children perfectly. I think people knowadays are more educated about negative psychological impact to children and therefore there is a change in parenting style which takes more effort. More quality time, no corporal punishment, more understanding and kindness and so on. The effort to raise children therefore has increased (fear based parentingis rather low effort). I think it is for the good. Those who are able to make that commitment raise the kids. (I dont say that negative styles don't exist, but society in general has improved on parenting styles)