To play devils advocate, if unanimity is required for guilt why doesn’t lack of unanimity mean innocence?
1. That outcomes should be binary, i.e. "guilty" or "innocent" with no mistrials. 2. That outcomes should be decided by unanimous, supermajority, majority, or some other arrangements.
I don't think either of those arguments are especially fundamental. My point was only that it's a bit hyperbolic to view the whole hung jury rule as some sort of Bill of Rights violation.