Not surprising, made no commercial sense to me for Kia to sell or me to buy a car the size of the Stinger in 4cyl 2.0l, this is same with Ford they sell/sold the Mustang here in 4 cal Eco Boost as well how many of those sold compared to 5 litre V8.
Australia is a large country with reasonably priced fuel, most Aussies want there main car, large with good/higher performance. 4cyl although good these days just don’t cut it on long trips for power & comfort (I’m talking petrol only on this issue).
I’m have 8,400 kms on my 3.3TT GT & am averaging 9.5 litres/100kms, not bad considering I was getting 8.9 litres/100kms in my 2.4l 2013 Sportage Platinum AWD.
Kia AU should only offer V6 in the Stinger & if you want 2.0 litre drop down to the Optima range.