This is even more true when "progress" means fertility rates collapse. A culture that is not self sustaining will die, and far more quickly than most realize. It doesn't matter how awesome that culture is for a brief moment in time, it will cease to exist.

Amish have an overall fertility rate around 6, which is why there are now almost half a million Amish in America alone. They had less than half that in 2000. In a few decades, they'll number in the millions. If people don't start having babies then groups like the Amish will take over the world, very much turning "the meek shall inherit the Earth" into a completely fulfilled prophecy. In some ways it's perhaps even a self fulfilling one if it turns out that 'non-meek' behaviors result in unsustainable societies.

The Amish are an exception, one of the rare ones (along with the handful of protected, isolated tribes). The rule is that a technologically inferior group will get rolled over by a technologically superior one for the benefit of the latter.