Knew a guy who used to work for Optus, he said their business SIP service was constantly getting hacked and their strategy for dealing with it was just to eat the losses and give out account credit like water, because their infrastructure was so outdated and poorly designed that it was functionally impossible to secure.

Honestly, Ausgov should rip Optus to shreds for this... not only for the data breach specifically, but also as a critical infrastructure operator they should be held to a far far higher standard than an ordinary business.