Mate, it is clear you are not Australian by your other comments and you are projecting fears about "most people" with little to no idea what you are talking about.

Yes, we have less individual freedoms in Australia than places like the USA. Some of them are trade offs that have been pretty widely accepted, even though they might have been unpopular at various points. Australian's generally have more trust in our institutions than other countries, and the handling of the pandemic in 2020 is a good example as to why that might be. This is an app provided by a state (not federal) gov, that is open source, and there are various other gov mechanisms to verify how the data is being used. If it ends up being poorly implemented/used/abused, very likely it will be found out and become politically unpopular to the point where it will be quickly dumped.

Not sure where you live, but here in NZ we have similar systems and approach to Covid as Australia. Lots of people have been calling for a system to be implemented to allow people to self-isolate at home instead of a managed isolation facility. So when I say that most people would choose the option to isolate at home, I'm not pretending to think on others' behalf - I'm basing that statement on my experiences here in NZ and in discussion with others here in NZ which is fairly similar to Australia.

Having an app on your phone that lets authorities check if you're self-isolating sounds totally reasonable to me. When you've finished your two weeks isolation, you just uninstall the app and move on with your life. No big deal.