Yes… and “seeing” may come in different forms, from spectral analysis to microwave to radio wave transmissions. Bare in mind that those radio waves may have red shifted into the microwave frequencies (SETI may have been looking in the wrong place).

On the remote chance we do detect an alien signature, the source of it will probably be so far in the past that that civilization will probably also be extinct. And certainly too far away for us to communicate with it.