It's obviously not possible with existing technology but future developments in biotechnology might lead to breakthroughs in terraforming planets like Mars for

It's obviously not possible with existing technology but future developments in biotechnology might lead to breakthroughs in terraforming planets like Mars for human habitation. In any event, fewer rockets is not going to prevent the 6th mass extinction. The biosphere is degrading and fossil fuel consumption is still going up because the economists have decided that higher GDP is better than a habitable planet. Musk is a favorite scapegoat but he is not the problem. Modern civilization is toxic and will continue to generate toxic byproducts as long as the human population is increasing.