They'd need the system admins, CI infrastructure and code review team to be in a jurisdiction free of this kind of thing, and then treat all changes subject to laws like these as hostile
The alternative is sell software that everyone knows has backdoors. Pretty hard business case to make
All of our rights (other than the right to a jury for certain criminal trials, freedom of religion, the aquisition of property must be 'on just terms', the right to be a senator if you can vote, and the right to vote in federal elections) are in common law. This means that any new law can overturn those interpretations.
Personally I think Australia needs to push for a constitutional bill of rights. Unfortunately this is going to be a very hard battle to win, given the enormous requirements to get a constitutional amendment passed.