While it will be in the distant future, the sun will eventually become a red giant, ending life on Earth. And humans could certainly destroy themselves or go extinct via another manner in the much more immediate future. The latter's small window of existence places a [proposed} duty on transplanting and spreading intelligence elsewhere, even it must be in the form of artificial or technological based life.
There is no impressive sign or indication of complex life -- and especially intelligence -- elsewhere (locally) in the galaxy. (
Rare Earth hypothesis)
While some form of reverse
panspermia is remotely possible, that might have delivered hardy Earth microorganisms to other stars via
interstellar objects, there is no guarantee that complex life would emerge again on even an ideal world seeded by such. And the process might likewise take billions of years or require contingent developments like a temporary
snowball world, to accelerate it.
Ironically, in postcolonial guilt terms, it may be pockets of anti-capitalist Westerners themselves that want to revert back to a more primitive era and
forget space travel and colonization. But other parts of the world will still pursue the ambition regardless of how deeply the West might withdraw into its shell of virtue-posturing shame. Along with robots (and giant monsters), Japan has been obsessed with space for decades, and the bug has traveled to China, India, and other daydream centers of Asia.
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