We haven’t been disarmed, so your question is founded upon a false premise.
But, yes, there are probably fewer guns per capita than there were thirty years ago. It’s impossible to know for sure (because we didn’t have accurate figures thirty years ago, and while the figures today are more accurate, they are still not all that accurate for various reasons), but that is likely. There was a significant decline in the late 1990s and early 2000s, but that’s corrected since then.
Handguns have never been all that common in Australia, but those are likely still as common per capita as they were thirty years ago, partly because of that (it was an unusual choice then, and still is). Where the significant decline is, is mostly in low calibre rifles and shotguns. There’s less ‘casual ownership’ especially in rural areas than there used to be (there was never all that much in urban areas).
If 75% fewer households have guns now than before you were disarmed decades ago, then saying Australians were disarmed isn’t a myth, and an increase in some people collecting rifles doesn’t make up for what was and for the likelihood that pistol ownership would have greatly increased during these decades of new immigration and unease.
Here is an explanation of the many rules and hoops to jump through and the limitations while owning, and the expense of it.
https://www.twclawyers.com.au/gun-laws-in-australia/
Are you allowed to legally carry a concealed handgun in Australia?
You need more guns.