I'm finding it hard to see a level of equivalency with these two actions.
The Chinese ship was there to surveille Australia's coast.
The Australian P8 was there to surveille the SCS.
Australia monitored the Chinese ship off the WA coast and didn't approach it.
China J16 dropped chaff in front of the P8 potentially destroying the engines.
There's probably a level of information that we're not aware of here. Like, exactly where the P8 was and what they were watching and listening to and, what an Australian submarine may or may not have been doing shadowing the Chinese spy ship.
I think China are very lucky that the chaff didn't destroy an engine and bring it down.