With the greatest respect, this thread runs the risk of encouraging people to discuss a subject about which they have no specific knowledge, express opinions based on “instinct” rather than evidence, assume that the aborigine peoples of Australia were backward, incapable of traversing their own land and ignorant of other tribes.
20-odd minutes of Googling is all that is needed to show that Aborigines built sea-going craft, that Tasmanian aborigines are known to have travelled by sea to Western Australia and King Island. That they carried men and women, as well as fire, aboard their craft. That is, they were skilled builders and mariners.
What this means for this thread, I don’t know. Aborigines initially walked to Australia, and later Tasmania, across land bridges that were submerged as sea levels rose. Aborigines have inhabited Australia for some 40,000 years.