I can tell you it's extremely easy to get an exemption to go overseas provided its for family reasons. And I can tell you it's extremely easy for foreigners to come to Australia provided there's a valid reason. I just met 12 university baseball players visiting a university in Australia from the US. They had been in Australia 8 weeks they said. That's 12 less seats for Australians.
most people coming into Australia are not even Australian or residents.