If you want a perspective from a person who intentionally chose not to have kids out of lack of interest, I think there is a simple explanation. Throughout history, there have always been childfree individuals, both male and female. You can see this reflected throughout history in practices such as consumption of abortive plants, use of animal skins as condoms, and even infanticide. The difference now is that people who don’t want children actually have the choice and access to highly effective means to prevent them. Liberal societies just happen to promote the greatest access to contraceptives and socially accepting attitudes towards opting out of parenthood.