One thing this comic misses and is silly is that billionaires would die without the working/slave class and they know it. They need someone to produce their food, their luxury goods, nd maintain the machines. They don't have that in space or mars. If the atmosphere becomes literally poisonous they will probably build a dome around their mansions.
The rich don’t do any work and don’t buy what they sell
They can easily be a planet away and still extract wealth from the people left behind. If pollution causes people to die quicker it doesn’t matter to them
If pollution causes scarcity then they become richer
If pollution causes extinction then they are dead so it doesn’t matter