at those prices if QFlink getting reasonable loads then they are making a good profit on these routes.
Better to look at a route like SYD/ABX where there are 3 airlines flying QF, VA & ZL & longer sector than SYD/TMW.
Had a quick look at VA & fares from $137 inclusive of taxes, one way.
Couldn't see the ZL fare, who would probably have lowest per seat costs & possibly lower average fares.