You say it's for the benefit of "decrepit old men," but the fact is that more and more of the globe is being lifted out of poverty and living more comfortably than ever before. The unfortunate fact is that global warming is an unstoppable force now, humans would have to go extinct for it to waiver.
I'm not saying we should do nothing, but I am saying that your framing is exactly why no one listens to global warming advocacy. We are powerless against it, not because of governments, but because people are living better and no one is going to sacrifice that; and even if they did the math doesn't add up to reverse course. The people that say we should all be sacrificing are often the richest among us that don't even know what sacrifice entails, contrary to your point.