If the government hasn't used divestiture powers to break up Coles & Woolies and the absolute behemoths they've become, can't see the government even considering touching the airlines.
Meanwhile NZ have threatened it for their supermarkets, but seem happy to maintain an airline monopoly. In terms of cost of living pressures, the former is far more critical to the most venerable.
Accounting for inflation, flying is cheaper today than it was when Fels was running the ACCC. Cost of staples like bread and milk, not so much.