Presumably they mean "populate Mars and thus avert human extinction" but that's definitely counting chickens before they hatch.

maybe the billionaires could actually do something about climate change instead of trying to flee to mars. i doubt musk is saving space for me in his escape pod

But you don't understand. Car analysts since the early 90s have been saying that electric cars would become profitable and become a serious chunk of the market by 2020 because they all knew that musk was going to come along and show us how great electric cars are and save the world.