This is irrelevant and misses the point.

Even a completely 'trashed' earth that renders billions displaced or suffering amidst ecological catastrophe is still infinitely more hospitable to life than celestial bodies that are completely devoid of that benefit in the first place.

I was responding to the op saying that humans face extinction. I don't think that true. I think we could have the tech to live in "moon bases" here on earth once it has been rendered a desolate rock. And yes, billions will die.

Yes, a dead space rock with no resources will save us from our overconsumption of the resources of the one non-dead planet we know of.

Considering how this thread started, you're saying that we need to escape to the one place that hasn't been corrupted by capitalism?

https://www.youtube.com/watch?v=g1Sq1Nr58hM

But more pragmatically, neither Biosphere project was considered successful enough to make this workable on earth at any large, or even small, scale. There is still much more work and research to do here. Any attempt here currently has a hard dependency on the larger ecosystem to supply it with inputs.

Musk working on building moonbases on earth looks a lot like what doomday preppers are already focused on.