Guess one would need to factor in probability of intelligent aliens being stupid enough to want to communicate with an existential threat. Think about it. No other intelligent life exists on Earth because we wiped them out. We have a history of mass aggression against different races and tribes. Why would intelligent life want to take the risk of communicating with other beings that essentially were the survivors that wiped out all others on their originating planet? Why would they have such a suicidal tendency and ignorance?,(reply>), Yes, we wiped out other planetary intelligent life — or enslaved them. Furthermore, an alien time perspective may have allowed study of us over what we call millennia. Lex tempered his opinions with optimism. It’s as important to be pessimistic.