This is a good point. A lot of it to me is one experiencing an advanced level of human progression and relative peace and two seeing the awefulness that some people put up with and three seeing the massive widening of wealth disparity. If it was a situation where we just had the environmental challenges but society had progressed to a more equitable situation I could see it but then our environmental challenges would not be as great as they are. In addition if we were in a state where we had stabilized our population and was working to degrow to a level that was sustainable long term. Then it would make sense.