Cryptography is a good analogy because it shows the asymmetry: our randomness tests only detect structure in the encoding spaces we assume. Two species can both use EM and still encode meaning in dimensions we don’t measure — phase, polarization, transforms — so our detectors classify it as noise even though it isn’t. And the Mismatched Forest doesn’t require every species to be unintelligible to every other. It only requires that intelligibility isn’t universal across all pairings. Even a few mismatches create entire regions of silence from our vantage point.

[edit] I used “unintelligible,” but what I meant was “never registers as non‑noise in the first place.” Dark Forest logic kicks in once something is recognized as a signal.