"Breaking up the banks" takes us backward; it uses the powers of the state to try and create a Jurassic Park of big beasts, freezing capitalist development at a certain stage, which is taken to be the natural order.
With the torrent of revelations from the Banking Royal Commission -- sweet perversity that Turnbull has had his BEST NEWSPOLL RESULT IN 31! TURNED THE CORNER! HAD A RANDOM STATISTICAL VARIATION! -- there have come calls from some on the left to "break up the banks". This was a refrain taken up by Bernie Sanders in the 2016 primary and presidential campaign, a decade after the 2007-8 crash, for the lack of prosecutions or much transformation in the financial sector.
Australia missed anything like that. We would have got it, had the Coalition been in charge, and imposed austerity. But, as the commission is making clear, we got something else: a regime of poking, prodding, lying to, and bullying some less savvy and often vulnerable customers into borrowing more than they could afford.