When we hit peak population. This will be the next historical epoch which dramatically changes the fabric of society, because it will lay bare the finite nature of surplus labor, as well as dramatically skew the ratio of workers to retirees. It won't completely eliminate capitalism, but it will largely be the end of consumption driven economics, and will force more and more of this surplus productivity to go towards supporting populations instead of enriching a privileged few.

There will simply be no other option. In some places this will happen violently, but in many places it will be a slow but peaceful transition.