Realism isn't defeatist. We are, in fact, losing badly. That's just the objective reality. The issue now is much more than people want to think their current ways of life can continue; that is the real risk now. It's also true that everyone can take meaningful actions today and tomorrow to improve the situation in the future. To your point, the "well will just live even more lavish now bc there is no hope" mindset is very dangerous. But so is thinking we do not have to change. Anyone in anything like the industrialized world will have to shift how they live in the very near term.