It's possible that as civilizations advance, the technologies evolve through stages of stuff. Perhaps, in the grand scheme of things, civilizations emit "electro-magnetic radiation with signs of intelligent use", then move on.
I'd say that it's very likely that there are no civilizations that are at the exact point at which we've arrived technology-wise. And even if they did, the closest star is - what - several light years away, so when we see their LIGHT, we are seeing light that originated four to eight years ago.
But The Milky Way galaxy is 105,700 light years across . . . If we were to detect "electro-magnetic radiation with signs of intelligent use" from a star on the other side of the Milky Way, it means that THAT civilization is where we are NOW, 26,000 years ago, which means their technology is 26,000 years ahead of ours NOW.
And that's just THIS galaxy. Scientists think that there are probably between 100 billion and 200 billion galaxies out there.
The closest known galaxy to us is the Canis Major Dwarf Galaxy, at 236,000,000,000,000,000 km (25,000 light years) from the Sun. The Sagittarius Dwarf Elliptical Galaxy is the next closest , at 662,000,000,000,000,000 km (70,000 light years) from the Sun.
The Phoenix Dwarf Galaxy is 1.44 million light years away, an unfathomably large distance . . .