I don’t think it matters as much if what you do in actuality ends up making a significant difference. What matters is that you did what you could. From the perspectives of future societies, you and I will be blips anyways, so that’s irrelevant. But how can one be contempt with knowing that they didn’t try to make a difference, and that their mark on the world disappears when the energy has left their body and their corpse has been burned and buried, I do not understand, because if you don’t (try to) leave anything of value behind, your existence is practically for nothing, except for maybe even a net negative.