Mobius does have a good point here. Unlike the Vasudans, Terrans didn't have to get off of their home planet or out of their home system in a hurry in order to acquire necessary resources. We live on a fantastically resource-rich planet, and beyond that, the Sol system has all sorts of avenues for materials exploitment and development. We know from FS1 that the external Terran colonies weren't all that old in the grand scheme of things; Sol was still described as containing the vast majority of Terran manufacturing capabilities. I'm sure the node collapse curtailed at least some activities due to the cessation of outside resources, but the inhabitants of Sol still had a hell of a lot to work with, not to mention hundreds of years of established manufacturing bases that the colonies couldn't even begin to approach.