Australia's population is, yes growing exponentially , but it always has. This is why it has always had roughly 25% of its population as immigrants, if you have any grasp of maths past year 8.
In fact, after word war II, the absolute number of annual immigrants was the same as it is these days...
"Aussies" as opposed to people in Australia that are nt Aussies. I would say only maybe 13 or so million of Australias population consists of "Aussies"