It might just be my Millennial nostalgia playing tricks on me, but it seems to me that there was something of a fad for all things Australian around the 1980s, at least from my perspective as a kid in the US. Here are some of the events/cultural products I was aware of as a kid that made me think of this pattern:
What was going on in--or with--Australia that prompted all this Australiana that reached me all the way in Kentucky? Or am I just imagining a pattern that isn't there?
I'm order to promote and embolden the Australian Film industry tax breaks/schemes were introduced that have investors in productions a greater than 1:1 return on their dollar. This meant Australian Film companies would get funding from anyone needing a tax write-off got their best leverage by funding a film. So now you get an industry who will make anything, because they have the money and need to use it. This leads to some very bad movies and a few good ones.
I worked with a couple grips who started in the 80's and while they got paid they were adamant Australian Cinema took a huge reputation hit because they just made whatever they could and so much was trash. The few successes didn't cover the losses and the tax break was removed, from what was above 100% claimable, to something closer to 70%. Someone may be able to provide the exact taxation rules that covered this at the time
How does this effect Australian Popularity? Australia is making digestible content and some is good, so with enough content the cultural exports are remaining in the Zeitgeist, and other content borrows from that influence to make and use that momentum to also profit/establish themselves.
It was more abundant; a decade later using the same national identity established in the 80's is used by another export and became extremely popular, Steve Irwin renewed interest and fascination in Australian Outback imagery. While not from the 80's it certainly reminded people of the existing influences and content.