1. Renting is around half the cost of buying
Not a bad argument. If people were genuinely able to save the difference, it would work out to be a good choice. Consider too that buying removes future rent rises.
This is true, especially in established suburbs. As an example, it would cost $850K to buy the place we rent now on the harbour. At 80% deposit that's at least $4000/mth mortgage, $2000/qtr strata. etc.
We rent for $2200/mth. That's $2000/mth in saving, to absorb any future rent rises.
The important thing is to invest the difference, and not just spend it.
5. Living at home/renting = Freedom
See the world! Don't worry about the future! Never mind that if you wait another 5 years that home you want might cost much more than it does now. Never mind that by waiting longer to get a loan, you'll be that much older when you do pay it off, and it's likely to be larger anyway. And of course, if you rent, you don't have to pay rent while you're off traveling (do you??).
No, exactly the opposite. See the world, while investing the different in rent saving in the future.
Freedom to move easily as well. Moving PPOR's can be quite a hastle.