It's ignorance steeped in a racist, settler colonial national identity. Education is very poor in this country - even my generation (late millennials) grew up being taught about white "explorers". School mostly skipped over what really happened to Indigenous Australians and when they were talked about it was only in a "oh isn't their culture so interesting" type of way. Australian history in high school was that Howard-era whitewashed shit about Gallipoli. For most Australians, this is the extent of their knowledge about Australian history. They don't study it at university and they have no interest in self-study so they just eat up all this garbage feel good shit about Australia being a completely wonderful country where any disadvantage is the fault of the individual. They literally do not understand the connection between history and what is happening today, it just completely goes over their head.