I think myself and the other commentors in this thread are trying to figure out who or what you are arguing against. Where are you reading that anyone wants to get rid of technology? Why do you think a "well kept earth" is incompatible with going to other planets? It really seems like you are inventing an opposing argument and only considering a very narrow list of options you've created yourself. As I re-read your comments I'm inclined to agree with ThatFanficGuy.
My point is that our current levels of resource use are sustainable, because our current levels of use are part of a system that has, and will continue to, adapt and change when it is needed to. If we artificially use less resources, we do nothing but hurt ourselves, and any attempts to artificially restrict resource use will do more harm than good.