Australia

The Government literally won’t divulge the details of what the Voice actually entails.

That is miss-information propagated by the "No" campaign. The governemnt absoltuely has divulged what The Voice entails, and it's really simple. These words will be added to the constitution:

In recognition of Aboriginal and Torres Strait Islander peoples as the First Peoples of Australia:

i. there shall be a body, to be called the Aboriginal and Torres Strait Islander Voice;

ii. the Aboriginal and Torres Strait Islander Voice may make representations to the Parliament and the Executive Government of the Commonwealth on matters relating to Aboriginal and Torres Strait Islander peoples;

iii. the Parliament shall, subject to this Constitution, have power to make laws with respect to matters relating to the Aboriginal and Torres Strait Islander Voice, including its composition, functions, powers and procedures.”

Let me make it even simpler:

There will be a group of people authorised to give a small speech on indigenous issues when parliament is in session and occasionally have meetings with relevant politicians/government workers.

The government will do their normal job (passing laws, etc) after taking into consideration what was said.

It's not complex. There is no risk. We're not giving Indigenous Australians some kind of exclusive right. The reality is anyone can write a letter to a politician, and if the letter has any merit at all a staff member will ensure the politician reads it. If the contents of your letter are actually important the politician will even meet with you in person.

The only thing that this changes is The Voice won't need to have their message approved by the staff member. I suppose in theory, that could result in wasting a few minutes of our politicians time... but I doubt that will happen. The reality is sensible people will given the power to speak for all indigenous peoples, and they will only talk about the most important issues affecting indigenous people. They will have an endlessly long list of points to bring up, and they'll pick the most important ones - which will never be a waste of time to bring up in Parliament.

At the end of the day it's a matter of respect. It's a formal process to do what is already being done informally. Indigenous issues won't need to be raised via back channels anymore.

A few details, like how many people will be on The Voice and how long they can speak in Parliament for, etc are still to be decided on, but none of those really matter. Does it matter if there's ten people or fifty in The Voice? Only one of them will be allowed to speak in any given parliament session. There's generally a 15-20 minute time restriction on anything raised in parliament, and I'd expect the same limit will be applied to The Voice. But if they allow 60 minutes instead... honestly who cares. By not putting it in the constitution the government is allowing those decisions to be changed without going back and doing an entire referendum all over again.