If Australia’s second-largest telco, Optus, thought it would minimise a scandal by saying it suffered a customer data breach on the national day of mourning marking the Queen’s death, the tsunami of government rebuke, customer angst, and law reforms has proved it wrong.

The Optus breach, in which a cyber criminal snared the personal details of up to 9.8 million customers, is shaping as a moment of reckoning for Australian businesses, as they are forced to account for, and ultimately take responsibility for, their insatiable appetite for customers’ data.