Civilization collapsing doesn't equal to species end. A gamma ray burst or yeah something that has already happened in the planets past, a big enough asteroid hitting us. Can mean the end of the species.

Of course civilizations collapse should be avoided even just for the reason of avoiding lots of people dying. We shouldn't completely discard expanding into space either. Our population and civilization is big enough that both things can be done at the same time.

Working towards both will probably provide a better overall goal for common people as well instead of currently working just to line the pockets of CEOs and pedofiles.