Exactly: which is why the BILLIONS spent on SETI and other searches for intelligent radio signals have been such a monumental waste of money. Even if we DO detect an intelligent radio signal, (a) the civilization that transmitted it has come, gone, and been replaced by several civilizations in the time the signal took to get here; and (b) any reply we send back will arrive long after our own civilization has come, gone, and been replaced by several civilizations. It's irrelevant given the enormous scale of the cosmos when radio signals are restricted to the speed of light.