No matter how we look at the world situation, the options don’t change. We can live better individually and reduce the lifetime of our species; or we can live less happy and shorter lives individually and prolong the lifetime of our species. The option of extending the lifetime of our species is rapidly becoming unavailable to us: Soon we will have done too much damage to the Earth’s biosphere and supporting systems for even the most miserly people to survive.
The preferred option, living better while increasing the lifetime of our species, is denied us because much of the world’s population depends on Nature for survival while humanity insists on sabotaging the natural infrastructure that keeps our planet habitable. We might salvage this option if we had the energy and technology to create artificial environments for the entire population, but we have neither; and we probably wouldn’t have enough time left to implement such a solution even if we did.
I can’t help but return to the aspirations of the space community when faced with such dire prospects. A variant of the last scenario is the opening of a new frontier that would provide access to more resources (including energy) and reduce the human load on Earth by moving people to other worlds. Whether those worlds are planets or asteroids, artificial environments will need to be created for their inhabitants. Again, we have a timing problem: Could such a solution be implemented in 40 years or less?