I think there is a big difference, experientially, between living in a country with social or political problems, and living in your own country amid social and political problems that you perceive (rightly or wrongly) as not always having existed.
There's a kind of suspension of disbelief that occurs when you're not entirely integrated in a society, either because you don't fully know and appreciate the history of the social environment in which you find yourself, or don't take it as personally as you would in the country you grew up in, or, at the other end of the spectrum, because you don't understand a word that's being said around you. I think as a comer-in you are more able simply to accept without undue judgement what the status quo is. Having infrastructural, cultural or linguistic barriers to do battle with on a daily basis frees you from the burden of considering whether the economic theories underpinning local healthcare delivery are sound, misguided or just plain corrupt, for example.
For people (like me) who are engaged in a long-running conflict between wanting social justice and wanting just to be left alone to work, raise children and grow vegetables half-way successfully, removing yourself from a situation where you are so familiar with the issues that you're in a permanent lather of anger and disappointment can be a great relief and a good life decision.
I agree that Australia has its problems, but I can see why someone who is heartbroken at the changes in their own country could happily enjoy the quality of life a sought-after professional could enjoy there (or indeed most places). I lived in Japan in the 1990s, which certainly had (and has) its problems, but the minimal amount of Japanese I acquired enabled me to focus on temples and bamboo forests and okinomiyaki instead of economic instability. There are worse ways to live.