Basic human nature is to further the species through population growth. It's literally the only thing that everyone can agree on as being "why we're here". Ever

Basic human nature is to further the species through population growth. It's literally the only thing that everyone can agree on as being "why we're here". Every instinct ingrained in every living creature is to produce offspring. Telling people to stop producing offspring goes against basic human nature, and requires a pretty educated populace in order to understand why they have to stop this instinctual process.