You don't need to have a high HDI society with free market principles and individual civil liberties. The requirements for limiting population are even lower. You just need to eradicate extreme poverty and provide decent healthcare and education. Most countries in the world are already on the path to meet these requirements (including major ones). Birth rates are in free fall across the world [1]. There's no one to get on board with "my ideals".

[1] https://www.youtube.com/watch?v=QsBT5EQt348