I agree with your assessment, but it's not an ideal world and unless CASA mandates minimum hours then it is what it is.
What would happen IMO if there was a minimum hour requirement, is the same guys that drag the T&C down for instructing would hang around the charter operators in the cities doing things for less. Some would head north and do the same thing to get a quick couple of hundred hours to get home.
They would beg scrimp, cheat and steal the hours until they could fulfill their requirement to stay home.
So really nothing would be achieved, nothing at all.
Provided they pass the same flight tests and exams, they have a licence to scare. Perhaps the regulator needs to increase the flight test requirements or change the training syllabus?
Just a thought.