Um, dude.... that is based on observing only ONE intelligent species, and any generalizations based on a sample of ONE are very suspect. Indeed, to assume respect for rights increases with time you have to focus mainly on the West and ignore about half the world.
Aliens, on the other hand, could be very different from us; so different we may not be able to imagine or comprehend how much so. They might be extremely cooperative and respectful of each other within their own species.... and at the same time have decided it is in their best interest to exterminate all sapients not of their kind. We have no way of knowing.