The NRT runs from Sydney are usually full of super senior cabin crew who have no concept (painting with a large brush here) about working - they merely go to collect yen and come home. QF management are aware of the problem however hands are tied by unions etc (hence the occasional voluntary redunancies aimed at removing the dead wood).
As a crewmember it is often noticeable - unfortunately, I do not think QF can be seriously bothered about fixing the problem so in the short term at least the it will not go away.
Of course this does not apply to everyone, there are some excellent cabin crew out there, it is just rare to get many of them on super senior trips.
(And yes from my experience the QF Japanese and QF Thai cabin crew are generally excellent they are vastly more polite - the QF Thai cabin crew even outperformed the locals in EP's training on the day i saw them in action)