If we are the only ones in the galaxy then there’s no Galactic Federation that the Israeli officer told us about just few days ago. And I think your numbers are a bit wrong. The actual numbers are probably closer to the Optimistic ones. Not because I’m an optimist but because you didn’t take everything into account when calculating your numbers. Also, what about alien civilizations that make it to type 3? And what about civilizations that can bend space and time to travel much faster than light? And what about the probability of a civilization hiding from us and not making an open contact for various reasons? If they can travel here, they sure as heck know how to hide. I would!