Can a man support a family of 5 on minimum wage in Australia, or did it stop working?
This is the list of awards: https://www.fairwork.gov.au/employment-conditions/awards/lis... it's pretty extensive
Each award is also complex, and covers a range of issues in the employment. For example, this is the Professional Employee award: https://awards.fairwork.gov.au/MA000065.html just working out what the minimum wage would be for a graduate engineer with 2 years experience is a complex, detailed matter.
But yes, probably, for most professions you could reasonably expect to support a family of 5 on the award, depending on location and definition of "support". Affording a house would largely depend on an additional inheritance, though.
Tell me a place in any Western society (outside of run-down rural areas/flyover states) where an average employee (i.e. no ultra-rich tech hipster bros) is able to afford a home before the age of 30 purely by his own savings and income. That is frankly no longer a reality for most people.
It is perfectly doable, even common, to buy a home in low and medium COL areas without any assistance from family, living or dead. The fact that you can't do this in NYC or SF is not an indictment of anything other than NYC and SF.
But there aren't any jobs there, so you're going to need an inheritance to support your family of 5.