It was common enough in China that the government had to say "don't do this".I never said it didn't happen, but as you said it wasn't acceptable or near as common. Similar to the concept of murder or rape happening while being unacceptable. Doesn't mean I think murders and rapes are going to stop and we all get to never face reality again. It shouldn't be easy or simple for everyone to be a virtuous person if the virtues are truly exemplary.
Like Android Raptor said infanticide in Europe only went down once contraceptives and abortion became more widespread and socially acceptable.
But for some reason "family values" Republicans are violently opposed to not only abortion but Sex Ed in general.