"IS has come to their (The Feds) rescue"
That is a wild accusation!
You don't honestly believe that the Oz authorities are pleased with this situation do you?
Yes and no. Depends what you are classifying as "the authorities". Obviously the police and ASIO are not pleased, as you'd expect. We've already had two police officers put in hospital after an IS-supporting nutter in Melbourne attacked them with a knife. Said nutter is now dead, due to a bullet in an inconvenient location. Moral of the story: if you're going to attack armed police with a knife, make sure you kill them before they can reach their guns. Anyway no, the "authorities", in the sense of the people charged with actual intelligence and enforcement work, are not exactly chuffed about IS.
The federal government is another matter. I don't think Abbott is on the blower to al-Baghdadi saying "Onya mate! Keep up the good work!" Nor do I think the ministers are creaming themselves over beheading vids or anything like that. What I am saying is that in public relations terms, this new "War on Terror II - What Could Go Wrong?" is a godsend for the government because it enables them to swing their balls around and promise to be "unflinching in the face of terror", instead of constantly backflipping and blithering about the domestic policies they were trying to introduce before they got their arses kicked. It's a distraction from the shit they were fucking up, and a way of them getting some cred back.
Am alleged plot to behead Australians was recently uncovered, they have some citizens as fighters there, including that guy who let his son hold up a severed head. I don't know exactly what specific prohibitive restrictions 'The Feds' have imposed that you are complaining about, but they have good reason to be jittery and are wise to tighten up and close any gaps in the armour, if they think there may be a danger. Sure it sucks for the rest of the people, but surely they reluctantly gotta do what they gotta do to protect their citizens.
Funnily enough, that alleged plot was discovered, monitored and dealt with under the current legislation. That tends to suggest that the current legislation is not entirely inadequate. This shouldn't be surprising since we have been through this shit before, so some thought was given to the current legislation.
Now it may be that there are some things in the legislation that could beneficially be changed. As I said, this happens from time to time. However, you would expect this to happen after the changes were subject to a fairly thorough review. These ones are being rushed through, or at least they'd like them rushed through (have got some already). That's a concern because a/ our Attorney General has a history of trying to introduce frankly idiotic changes to existing legislation and b/ any time someone tries to restrict civil liberties, without adequate review, by dragging out a useful bogeyman it is generally a bad look.