Australia is a lot less able to expand than people realise. Water supplies are a major problem. You don't have to travel that far before you get into semi-desert regions. No inland water supplies makes it unrealistic to form major regional cities to take pressure off capital cities.
I have traveled a lot due to my husband being in the army until 5 years ago. I have lived in 4 different states. Very different cultures between states, and very different between big cities and mining towns. Western Australia was closest to being a foreign resident I ever will be. They have a surprising amount of hostility towards East Coasters. I was there during the mining boom for 2 years and many wanted to secede from the rest of Australia. We were "sponging" off them apparently, via funding being taken from WA profits to prop up other parts of economy that were struggling at the time. (Very strong Aussie dollar -> Aussies going overseas for holidays, tourism industry crashed, online shopping soared, local businesses going under etc.)
I think modern society has become like that everywhere. Especially in big cities we're all too scared to talk to anyone just in case they're a weirdo, a criminal etc. Modern media and entertainment industry has made us extremely paranoid.
I think many people have become like me from moving around too much. We have to move for jobs/ education needs way too much. Cutting ties with people you have got close to does hurt. It does become easier just to withdraw and not take the risk to get out there. One of the reasons my husband got out was because we were concerned about our boys that way.
In the little town I am in now people are much friendlier overall. It is distance and lack of public transport that makes non-drivers like me unable to participate in activities much.