I think you're right. Executives need to be held personally liable, it's the only way to ensure that they take these issues seriously.
In cases where there is intentional wrongdoing, existing laws already make complicit people liable both to civil action by people harmed, plus criminal or civil penalty provisions by ASIC (or the ACCC, depending on the industry and conduct). As a plaintiff, you typically join them to increase your potential pool of recoverable assets for your clients.
The same is true if there are breaches of the Australian Consumer Law, and the person has a particular level of knowledge that is below intention.
In cases of pure negligence, like this, if the negligence rises to a criminal standard, then criminal laws and penalties already apply. How and when this works has been a topic for over 50 years, since Tesco v Nattrass in the UK.
In other words, there are already very significant legal mechanisms in place, and by and large they work - and not all of them involve having executives personally liable. In any event, many already do, and this has been worked out carefully over a long period.
When you really think about it, that is a VERY scary thing.
Quite literally it goes:
"If I do this illegal thing myself, I'll get in lots of legal trouble."
"If I form a company and do the illegal thing, I'm safe."
I think the limited liability is for debts to creditors and shareholders, rather than limited liability against criminal or other behaviour.
Maybe I’m wrong, but as I understand it, Australian law treats a corporation as a person and the directors are answerable if the corporation breaks the law.
The real problem (as I see it) is that a company the size of Optus can afford to defend their behaviour for so long that enforcement itself becomes a burden. The closer you get to the CEO and board, the more they will spend shareholders money defending themselves.
Actions without proportional consequences were never going to lead to anywhere but destruction. Folk psychology told us that was likely (however much virtual-economists feigned ignorance). Empirical reality has confirmed it.