additionally to the Expense, in some situations (for example in a burning house) where the radio reception gets bad an analog radio degrades better: the signal gets noisy but you can propably still understand what's said, and you can ask for repeats and piece together something out of a few retransmissions.
With digital radio on the other hand, a bad signal results in lost chunks. There the transmission is clear until it gets choppy and that's a lot harder to make anything out of.
BTW, does anyone know why aren't there codecs that would increase the speaking latency but spread out the information over a wider range of the signal, so that the lost chunks could simply be reconstructed from last and the next chunks received?
That's just another ECC and things like raptor codes to exist, which could achieve analog-ish characteristics in digital transmissions.
I suspect this kind of encoding works badly with encryption, as decryption needs a perfect preimage otherwise the decrypted message will simply be garbage. Also, even a slightly increased delay makes for very awkward conversations.
With digital radio on the other hand, a bad signal results in lost chunks. There the transmission is clear until it gets choppy and that's a lot harder to make anything out of.