It's a perfect example of Tall Poppy Syndrome, and Australians are the world's worst offenders.
Definition from Wikipedia:
Tall Poppy Syndrome (TPS) is a pejorative term used in the UK, Ireland, Australia, New Zealand and Canada to describe a social phenomenon in which people of genuine merit are resented, attacked, cut down, or criticised because their talents or achievements elevate them above or distinguish them from their peers.