With the greatest of respect there is only one way you will "get through' to the Qantas management.
That is to affect their sales and marketing.
If you cannot affect sales, then they can do what they like to you with impunity.
The elephant in the room is safety.
None of you can make a case that says Qantas is compromising safety. (disclaimer :- I wouldn't know)
Therefore you are powerless unless and until there are multiple crashes where "pilot error" and/or bad maintenance is a factor.
In my very humble opinion, your best bet is that this happens to an overseas airline before it happens to Qantas.
Think the space shuttle disaster. Overseas airlines are busy working out how little maintenance is required and how unskilled the crews need to be.
Ansett, TAA, Qantas, worked on the other approach with defined standards set by professionals. These seem to be under attack with the excuse being given for the reduction of "new technology".
I don't want to be the first to find out where the boundaries lie.
For example, I fly with charts and a full flight plan as well as a navaids plan and alternates etc. Even though I have the entire plan loaded on a GPS on my wrist. - At least it keeps my (nervous) passenger busy ticking off times and locations. But then again, I'm only a humble VFR pilot.