Other than as very early stepping stones to some kind of extra-solar settlement on a less "fragile" planet, these things are no sort of solution for human futur

Other than as very early stepping stones to some kind of extra-solar settlement on a less "fragile" planet, these things are no sort of solution for human futures. They are all far more fragile than earth and no settlement on mars, the moon, the Lagrange points, or any other body in this solar system will last long if something like an asteroid wipes out civilization on earth.