A 380 with restricted capacity is exactly what is needed on such a route, economics aside. I did the trip recently and on the way back with a full load, half of the Economy toilets were inop in the last couple of hours due to full waste tanks. Many hungry and bored pax were up and about in the last few hours and having more space would most welcome to both passengers and crew.
If you want to do the sums for a 380 then look at the OFP for the inaugural flight there and back that was operated by a 380. The load on both ways was not more than two thirds full if I can recall correctly.
This is nothing more than a headline grabbing exercise. The 380 starts in December and Qatar starts direct AKL in Febuary with their triple and then eventually using the 350, which I am sure beats any of our 77L airframes hands down.