I reckon they used to say this about political institutions in the US and the UK. It starts with Departments (which have become politicised in Australia over the past decade) and moves down the chain."Capturing the AEC" is another thing that won't happen nor any attempt will happen.
The fiasco of the AAT is an example where this kind of thing could easily happen in Australia.
Electoral Commissioners are appointed by the Governors and it's not too beyond the realms of possibility of seeing politically appointed Governors making politically appointed Electoral Commissioners.
Governors are appointed by the King, so it really only takes a crazy king to start the demise of Australian democracy. Just because it hasn't happened before doesn't mean it's not a glaring-wide hole in the constitution for politicians to drive through.
It's worth learning and strengthening our democracy from observing what happens overseas, not just assuming it couldn't happen here because it hasn't before.