I think this has the potential to be big over the next few years. Imagine machine learning going nuts over every return for the last 7 years night and day for peanuts. Auto contacting people to provide receipts, it could likely audit a million people at once and not blink.
the amounts are visible on mygov or via your accountant if you like paying extra fees.
I'll have to look into it, surely someone has done an opensource implementation on GitHub that runs locally and doesn't need a third party.
edit:
Good guy Luke
https://github.com/LukePrior/Australian-Open-Banking-Data-Database
A single horseshoe crab, naturally deceased.
It was a great thing for Australia after some short-term pain, exporters saw how exposed they were to a single market and started to put effort into diversifying.