Not based on birthrates
It has nothing to do with video games or hentai
If you ask women WHY they aren't having children, they'll say shit like
"It would get in the way of my career"
"It would get in the way of my education"
"Not looking to settle down right now
"Too expensive
"I just don't want children
"Haven't met the right person
The way to raise birthrates is to FORCE women to have kids. Like how every patriarchal civilization in history has done