By window I meant the following: you said that " they have witnessed rapid economic progress in their own societies in their own generation, so they wouldn't understand the appeal of Western pessimism about apocalyptic and dystopian futures." If that is what is going on, then the next generation may not see that as much. If so, we have around a generation. I agree that if the economic progress continues at a fast pace that may not end up with some of the issues we have here, but in general developing countries have as they've neared parity with the developed countries had their improvement rates by many metrics slow down and come more or less into alignment with Western growth rates. Look at for example infant mortality levels and expected lifespan.