What happens when commercial capability allows ultra long haul Australia direct Europe bypassing the Asian & ME hub carriers?
Sydney and Melbourne direct to London would be a goer. There aren't enough people wanting Brisbane to Madrid to make it viable non stop, also not everyone wants to connect via London. Melbourne to Athens via Dubai save a lot of backtracking.
Emirates can fill planes from secondary cities such as Perth because people getting onto that plane are going to multiple destinations rather than just one. Effectively you combine several flights to different places on one aircraft, which if flown individually wouldn't be economic.