Constitution
The issue with the Australian Constitution is that, written in the context of federalisation, it’s focused on the division of powers between the feds and the states.
It hardly even considers the people it is supposedly “protects”, i e. us.
A good constitution, as any American will tell you, gives the people or a person the legal tools to fight against any government that might have it’s own interests ahead of the people, i.e. all of them.
Possibly that is best argument for the voice. If it had got up, the rest of us could have them clamored for the same rights as the indigenous population.