It’s one of the main topic of pretty good sci-fi series (well first two books are good). I don’t think it is real though. Fermi paradox is real, but most of deliberations on it ignore the time and space (which is pretty normal, human brains do tend to have huge trouble with those on a space scale). Human civilization is barely noticeable in tiniest of ranges in merely a century or so, and we are already on the brink of exctinction because capitalists and imperialist warmongers just can’t stop.