This feels like circular logic to me. "We are early because later on the universe will have been colonised", but we don't admit "We are not later alien members

This feels like circular logic to me. "We are early because later on the universe will have been colonised", but we don't admit "We are not later alien members of a grabby species because... ?" By the logic in this argument, it should be "fishy" that we're not aliens living at a later stage of the universe, so I don't think this theory is complete. The expansion model seems to work though.