OPINION:
I'm from Australia. I'll lay odds this is primarily a pricing issue. The AUD us at 73c USD, but prices we see are often based more on 20c below the current USD. Plus GST of 10% plus import duties, plus distributor margins plus retailer margins, plus shipping costs. Prices skyrocketed by 30% - 50% in mid march when the AUD dropped to 57c. Despite now being at a 2 year high prices have not come down, or really stabilized.
Each new graphics card generation seems to have attracted an minimum of an additional 20%-30% on top of the previous gen.
Supply is currently an issue. Many retailers are moving away from keeping many items in stock. All retail stores are currently closed and places are moving to delivery only (Some saying permanently). Shipping is also broken. Australia post have ceased standard mail delivery in many areas, and parcel post can take up to 6 week for items distributors have in stock, and many months for items they don't. All carriers are experiencing minimum 14 day deliveries for all components I've ordered. (Cases, SSD, cables, HDDs, wifi adapters, RTX 2080 Ti, monitors etc).
True, number of flights have drastically decreased and our relationships overseas are Strained. But whilst contributors I don't think they are they primary factors.
It's not the first time. Australia has a habit of not selling items. They've skipped previous gen CPUs for example and some HEDT items. Some of the top end motherboards have also been excluded from Australian sale. For example, Z motherboards used to be all the rage, and affordable up to 2017 when prices effectively doubled. $240 would get you a good quality, full featured Z board. Now, they are anywhere from $500 - $2000, even more for AMD. Many have been forced to drop to 'B' motherboards just to be able to afford one.
A large proportion of the population is now unemployed. I forget the current percentage figure, but another half million are expected to lose their jobs by Christmas. So money will be extremely tight and we are now officially in a recession.
A lot of factors I guess.
As I said before, I wouldn't be surprised if the RTX 3090 exceeds $4000 AUD.
(Based on personal experience buying components over the last 15 years @ around $13,000 per year).