I am a strong proponent of E2E encryption and the right for people to be able to communicate privately, however I thing Brandis is saying generally positive things. If Australia thinks someone is a criminal, and there is an agreed process to obtain a warrant (hopefully from a judge), I think that's fine. The NSA mass-surveiling Americans is entirely different, as are other similar tactics to spy on presumably innocent people. Warrants are good, especially with people actively making calls.
Sad to hear. Do you think he's actually going to hand-approve all the warrants? Hopefully it's still better than what the USA had with all the warrantless phone data aggregation.
