It's both and it has been that way since roughly the era of mass production of consumer goods and certainly after WWII, not just in Australia but pretty much wo

It's both and it has been that way since roughly the era of mass production of consumer goods and certainly after WWII, not just in Australia but pretty much worldwide. Many countries try to export their culture as a means of projecting soft power, some more successfully (or perhaps: aggressively even in some case) than others. The US simply have been the by far most dominant power in the last hundred years, politically as well as culturally. As for more recent developments, I'm not so sure about that. If anything, from my perspective due the influence of Spotify and Netflix and the wide range of these services provide, popular culture has become more diverse and less US-centric than it used to be. That said, in the Anglosphere, American influence is more pronounced than elsewhere because of the same linguistic and cultural roots.