There's a perspective problem here.
Australia Post doesn't make profits and losses, it provides services - and services have costs, not losses.
Expecting Australia Post to:
A) Deliver packages of international origin for free
B) To unprofitable remote/rural areas
C) AND turn a profit like a business whilst
D) For profit courier companies undercut them on profitable metro areas...
Well it's not going to work long term.
And post offices are more than just places to drop off a package you want delivered, lots of people use them as their local bank branch for necessary in person tasks - especially in the a fore mentioned rural areas.
Long story short, Australia Post should not have been privatised - it's an essential service and essential services are natural monopolies.