I think this piece makes a very good point and makes it very well.
One thing I wonder about, vis-a-vis SETI-style projects, is the idea the humans could identify extraterrestrial communication even after receiving it. I'm fine with assuming that extraterrestrial life is attempting to communicate with us and is using technologies we'd be familiar with (eg., electromagnetic radiation transmitting binary data) — until we ourselves develop some other technology, this is our safest assumption. But we should also assume that a sufficiently-advanced lifeform would transmit data near the information theoretical maximum efficiency, and of course, maximally-efficient data will appear entirely random to an observer who has no means to make sense of it.
One thing I wonder about, vis-a-vis SETI-style projects, is the idea the humans could identify extraterrestrial communication even after receiving it. I'm fine with assuming that extraterrestrial life is attempting to communicate with us and is using technologies we'd be familiar with (eg., electromagnetic radiation transmitting binary data) — until we ourselves develop some other technology, this is our safest assumption. But we should also assume that a sufficiently-advanced lifeform would transmit data near the information theoretical maximum efficiency, and of course, maximally-efficient data will appear entirely random to an observer who has no means to make sense of it.