How long has Qantas existed? Qantas knows full well how to run a decent, well respected airline, and has done so for many years. It is only the dickheads now in charge who don't have a clue. As someone said, as soon as they start coming out with inane management phrases instead of plain English, you know that they - and you - are in trouble.
We had the same in the UK. A well respected pioneering airline, with good pilot training, good standards, good routes, good customer service etc, and which had been going for 40 years. Everyone knew what to do, everyone was happy. Then a couple of new CEOs came in and 'suddenly' the airline struggled to compete, and went under only a few years after. They came out with phrases such as 'north of' instead of 'more than', and used to have meetings to decide when to have a meeting, I kid you not.
Running a good airline is not rocket science. You need 5-7 crews per aircraft, depending on what your route structure is, and you need your own ground staff and engineers. That's it.
If you contract out any part of it, you lose control and accountability, and therefore you cannot guarantee your service. During busy periods, the ground service companies - which are now run like sweat shops and with zero hours contracts - will also not have enough staff, because the staff they do have will have no loyalty to their employer or to the job, (no disrespect to those workers), so any busy times at the airport will be a total mess.