That's a very good point. When we first started listening for alien signals, we assumed that of course aliens would have TV and radio. In the few decades since then we have mostly switched to digital TV which has much more efficient (looks more like noise) encoding, and a trend of moving away from broadcast to YouTube, Netflix and podcasts is also evident (using both higher efficiency encoding and much lower transmit powers). And developments like 5G are intended to accelerate this development by using even higher coding efficiencies and shorter distances/lower power, as well as beam steering to directly target the receiver.
Perhaps civilisations only typically use broadcast communications for <100 years, a mere blip at galactic scales.
