We tried top down. Didn't work.
We tried bottom up. Didn't work.
The birth rates are declining in large part because of the expenses and time required to raise a kid these days. If life was perfectly easy for anyone to have a child, then the population increases. So, what - you’re going to kill extra children? Forcibly sterilize most? Purposely make life difficult so people lose interest?
This makes no sense at all.