Even assuming an absolute worst-case scenario climate-wise (no mitigations whatsoever, massive sea-level rise, etc.), Earth will still be dramatically more hosp

Even assuming an absolute worst-case scenario climate-wise (no mitigations whatsoever, massive sea-level rise, etc.), Earth will still be dramatically more hospitable to human life than Mars for the entirety of Musk's lifetime, and very likely his children's and grandchildren's lifetimes as well, barring some mass-extinction event like a nuclear war. Even if a colonization effort begins soon, living on Mars is likely to be extremely difficult for centuries -- we can't breathe the air or grow anything in the soil, our biology is likely ill-adapted to the gravity, there is no liquid surface water, etc. -- and the idea that there will come a point in the foreseeable future where it makes sense to escape there because it's easier than being here (because of pollution or whatever other reason) is difficult to fathom.