It seems like the matter is a "won't fix" since september 2020.

>Responsible disclosure history

>This problem was disclosed on 19th August 2020 to the Australian Signals Directorate, with an indicative expectation of a 90-day disclosure period. ASD communicated it to the ATO. At a meeting on 18th September 2020, ATO told us they did not intend to change the protocol, at which point we immediately informed them that we would make a warning to users public on Monday 21st September.