I understand that airlines can reassign a seat for operational reasons, such as making sure the plane is balanced.
But I've read a September 2016 article about airline staff from United Airlines in the US giving a woman a different boarding pass because she was a woman, and some men didn't want to sit next to a woman.
In Australia, for domestic flights, are airlines allowed to involuntarily reassign a seat on the basis of gender? Also, are such reassignments prohibited by the policies of the major players in domestic travel in Australia?