I would just like to remind people that in Australia the word some used by some people in their posts on this thread to describe the Indigenous nations are not too dissimilar to the use of the n-word in American culture to describe people of African descent. On an additional note the myth of all First Nations people being hunter-gatherers is just that, a myth. It was based largely in the Terra Nullius doctrine used to justify the cruel treatment and genocide of these people.
Now that historians are not barred from researching deeper into these topics there has been increasing evidence to find that they were mostly an agricultural society that built buildings and tools out of various materials (stone and wood) and sailed out into the ocean to trade with some nearby nations (including the Indonesian islands). They also had democracy and republics long before the Classical Greeks came along; governmental systems in some cases nearly indistinguishable from that of a single-chamber parliamentary system. They did engage with wars with the British (unless we are now considering armies smaller than 5000 in size as "skirmishing armies" which means we would need to remove most HRE nations) and they also traded with the Ming on at least four occasions between 1500 and 1650.
There were certainly still nations that were mostly hunter-gather societies that were forced to roam around due to the lack of resources available deep inside the interior desert of Australia, but these nations aren't in the scope of the upcoming EU4 update.
Essentially what I am saying is that you can be upset about some game features being bugged, or lacking updates, but this shouldn't be used as a continual excuse to pretend that these people had no impact on history in this time-period or that it is ahistorical that they are included in the game. And also what I am saying is to stop using that word to define these people.
Aborigines vs aboriginal is not the N word, and It's absurd that you would accuse me of that. Nor is it automatically invoking Terra Nullius.
A lot of what you say is technically and narrowly true, but presented in a throughly misleading manner.
Yes there were trade networks that had goods and coin go between some Aboriginal populations in the far north, and Ming China. But they were not started by the Aboriginal populations, it was Chinese and Macassans merchants coming to Australia, not them routinely going to Indonesia. They didn't embark on a trading empire, they used the coins they got as fishing weights. Signs are that their naval capacity was very rudimentary and largely limited to areas near the Torres Straights. Tasmania effectively lost contact with the mainland and lost the ability to refine stone tools. Which is not at all a far distance from the mainland, and the Polynesians easily covered far greater distances.
They had rudimentary aquaculture in a few niche areas, and cultivated plants in a Proto agricultural manner. But saying they were a mostly agricultural society is absurd. They were nomadic, their staples were hunting, fishing if they were coastal, and gathering.
Tribal democracy is clearly not the same as Greek democracy and you know it. Tribal style democracy has been pretty universal from the historical record. That is basically just how humans organise small societies of that scale.
They deliberately didn't fight pitched battles, which is what Eu4 represents. Professor Henry Reynolds, whose expertise in frontier warfare described their warfare against the British as an individual or small unit guerrilla warfare. There was resistance, but it was flatly not the fight a single pitched battle and occupy a province style of Eu4 warfare. Nor would there be an Aboriginal tribal commander marching thousands of troops into the lands of his neighbours to 'conquer' their lands. There was inter-tribal warfare, but there were no holding borders like Eu4. Some HRE states had small armies, but they fought and were organised similar to their larger counterparts, and would add their armies in coalition when called up.
But what do Aboriginal tags offer? Nothing. It is just ahistorical bullshit, of standing armies, and if you colonise Australia now you send a small doomstack around rolling over their conventional armies in a single pitched battles. If the Devs wanted them accurately represented, just expand colonial events. Tags are just dumb.
Anyway, as to the oral history stuff. They did record some stuff that has been verified in the historical record as having happened hundreds or even thousands of years ago, like major weather events. But that is still not the mark of a EU4 level civilisation.