The way I see it, human society is a statistical-mechanical system and we’re sources of noise.

So, if society is close to a bifurcation point or you personally are really loud (in case Xi Jinping is reading), then yes. Otherwise no.

Edit: I should specify that even if you can’t save everyone you can probably save a few people. The question I’m trying to figure out for myself is how big a bifurcation point to target.