However, we prefer the settings we have now. We like our cities where they are, we like the sea level where it is, we like polar bears and the Great Barrier Reef the way they are.
Selfish? Yes! But it is relevant because we are the ones who are changing the climate right now! So we are entitled to have an opinion about the changes we are causing.
If you think it's not fair that China and India have to deal with climate change, I agree with you. But life is not fair. As you point out above, there's no greater purpose to the universe, it just is.
If China and India don't want massive civil unrest, they better work on the problem. If you think moving billions of people away from the coast is easier than reducing fossil fuel emissions, fine, we can examine that idea with data. But political control is not a useful yardstick. Government is an important tool no matter what the plan is.
I have no expressed opinion on whether the attempt to make China or India conform to green western politics is fair or not; but those two nations probably do, and that's what's really relevant. They'll most likely experience bouts of massive civil unrest without regard to local atmospheric quality.
After that, the Hadean is a period about 4 billion years ago named mainly because (to life) it was hellish, but otherwise relatively self-contained (in comparison to the epoch immediately preceding it when space debris continued to pummel the planet).