Granted, the Aus government has a history of over-protective, arbitrary mandates (e.g. hot tap regulations [1]). I don't feel strongly in either direction, although I have an aversion to silly and wasteful rules.
That said, in the case of mandatory warranty policy, I can definitely see some merit. It definitely seems like certain appliances are being sold in a lemon market [2] (think blenders, etc), where the market is flooded with sub-standard, cheap products. These can become the norm and set overly low price expectations, making it difficult for good products to compete.
How this applies to top-end smartphones is another discussion. I don't see why it should be difficult for a them to honor the policy, given their focus on quality. What's important is that all companies honor the mandate, and compete on an equal footing w.r.t. consumer expectations.
[1] http://www.phaa.net.au/documents/130201_Hot%20Tap%20Water%20...