The crew of Destiny don't need to have a big moral debate over whether or not to help their descendants. If Novus is within range of the colony's gate then so would Destiny be if it was in orbit of Novus. Destiny just had to fly there and the colonists gate to Destiny then shuttle down to the surface.
Given 2,000 years and starting from a point where they already have working knowledge of ancient technology, including multiple forms of FTL travel, the descendant's population would be substantially more advanced than it is.