Earth post a super volcano would still be far more habitable than mars, same thing goes for a major impact event, nuclear winter and pretty much anything else t

Earth post a super volcano would still be far more habitable than mars, same thing goes for a major impact event, nuclear winter and pretty much anything else that doesn’t turn the atmosphere into a firestorm, boils the oceans and turns all land mass into lava… And if you get to the point in which you can terraform mars then fixing the earth would be again far easier unless all biomass somehow dies and there is no atmosphere left and earth somehow loses its magnetic field. At best mars might serve as a temporary lifeboat but even then if you have the technology to sustain life on mars you would be better off building protected habitats on earth.