I am in my fifties and a significant number of my friends and family opted to not have children. The children conversation use to come up a lot, mainly because parents refuse to believe that other actually do not want to become parents. Almost without exception, the reason those friends and family members opted to not have kids was because they did not want to. Only one person has ever given a nihilistic reason like "I don't want to bring a child into this fucked up world". Almost every said that they just did not want kids. Simple as that.