Not sure what is so hard to understand about this. Too many people choosing not to have a baby is a totally different and separate issue than whether people are allowed to choose to not have an unwanted or accidental baby, which is most cases is probably because they are not ready or can't support financially, made a mistake, rape etc.
Ideally, we want more people to be having kids that they want, when they are ready. We don't want people who are capable of adequately raising the next generation choosing not to, and we don't want people who aren't ready raising kids either.
Nothing conflicting about these stances for people who are capable of thinking outside of black and white.