Let's say stupidity prevails and Apple, Google and Microsoft build Australian spy support into their operating system software. What stops me from refusing to update from a pre-spying software version?
The "bad guys" will stick with today's versions of iOS, Android and Windows. Maybe in five years that could get to be a problem, but they might outlast the current government until someone else comes along who maybe has more sense. Or will they try to make non-conforming stuff illegal after a time, so any Android phone not capable of being updated becomes illegal?
I hope Apple, Google and Microsoft tell the Aussie government to stuff it. See how long the current leadership lasts after telling the public that they can no longer buy an iPhone, Android or Windows PC.