It's "for our safety".

For context, I'm Australian and have just come back after almost 20 years away, living around the world.

Safety is now the absolute most important thing in Australia above everything else. Sadly, it's now more important than enjoying life.

I'll be leaving, only come back to visit family from time to time. I have zero interest in living here.

Have you acquired alternate citizenship?

I did yes. It was about 7 years of paperwork and grind, but it was well, well worth it.

My 3rd one is well underway now too.

Both major parties have promoted these policies. The party in charge has been very effective over the past decade creating an immense atmosphere of fear and envy; the Opposition party believe there are too many votes to lose by not addressing this and have sacrificed a lot of their previously progressive stances to match the tempo of the right-wing. Besides both sides of government, the people pushing it are morning TV show hosts and, naturally, the Murdoch media. There are PLENTY of dissenting voices, typically on the grassroots level or among arts/media industries, but few of them are empowered to match the ferocity with which these other entities will go after them. Police raid journalists' offices and homes at worst, relentlessly harass them in the news or cover them in defamation lawsuits at best. There are a lot of Australians who do not want this current situation, a lot more who are afraid and misguided, and a small but influential fraction protecting their self-interests at the expense of the rest of us. If that summarises things.