Sustainability is absolutely impossible to achieve through capitalism, even if you instantly murder most all of the population, because of the very nature of how it views growth. It sees accumulation as being over wisdom and health, when it even considers the latter to be growth at all. Population is the way it is because of capitalism. Worse yet, we as a species are forced to do unethical reduction through war/murder/whatever if nature doesn’t take care of it for us, because of this “need” for constant accumulation. It’s a bad system. Don’t hate the player if you aren’t going to hate the game.