Great analysis Richard. I accept what you are saying about the crisis happening right now with a rapidly overheating Earth. The train we are on left the station decades ago. The heating we are in the throes of right now can't be stopped. Unless maybe nuclear war would bring on nuclear winter, with a lot of other very bad consequences.
Sorting out how such unprecedented global heating will impact our very complicated, interrelated, and technological civilization is a difficult project. I suppose the simple answer is that things will fall apart. There will be unpredictable twists and turns. It's not going to be an uplifting present-to-future transition.