so many pages....
for the OP, obviously things got pushy at the SIN lounge, may be a bit drunk and getting physical, otherwise security will not be involved.
and then is the court case, which obviously cost more for Qantas and that's why OP banned.
remember
1. QF is there to make money, status is just a mass tool to get more profits (repeat customers), you are not that special.
2. there are always other more important people than you, and they can take your seats, more important people includes CL, politicians without status, key staff of government departments, QF management, pilots and crew for the next job, and friends and families of the check in staff !
as for the domestic priority boarding, the good news is that the SYD MEL Commuters generally are quite civilised and very orderly, therefore they can generally board and seat on their seats quite quickly and for the on time departure, also most of them don't have large and lots of carry on bags... and the 737 is a small plane, all these reasons means priority boarding is not that emphasized anymore.
intra asia and intra USA flights, whereas people carry a lot of carry on, in that case priority boarding matters because overhead compartments get filled quickly and if you board last, there is a chance that you will have the bag stuck in front of you, or get checked in....and you can see for AA and UA etc they have very straight boarding groups, and they are strictly enforced !