I agree with most of what you’re saying but my thought was that digital broadcast signals are compressed and multiplexed so they’re likely to be much more compl

I agree with most of what you’re saying but my thought was that digital broadcast signals are compressed and multiplexed so they’re likely to be much more complicated than analog FM transmissions. I think they also broadcast to equivalent range at lower power, so I assume they have checksum bits in the stream so the decoder can reconstruct or reject a weak or intermittent signal. Then, if an entity trying to decode the signal had no framework for human communication the difficulty would be significantly higher because it would need to approach the data using a pure information-theoretical approach. Meanwhile I can (theoretically :)) build a crystal radio that “decodes“ analog FM in an afternoon.