"bandwidth negotiation" - HF paths are often unidirectional in the sense that you can interfere with station A without station B being able to hear. You can easily interfere with people you can't hear and autonegotiation mean you're autojamming without being aware of it. Not an issue with "human in the loop" modes. No application layer need for it anyway.
"spread spectrum" - See above, plus raising the noise floor means the death of entire weak signal modes.
"encryption" - Absolutely no need. Would be death of ham radio. Why bother with cheap ham radio licenses if you can just transmit anything you want but encrypted.
"the bands are mostly empty" Buy a better antenna LOL.
"spread spectrum" - See above, plus raising the noise floor means the death of entire weak signal modes.
"encryption" - Absolutely no need. Would be death of ham radio. Why bother with cheap ham radio licenses if you can just transmit anything you want but encrypted.
"the bands are mostly empty" Buy a better antenna LOL.