traditional aboriginal people might not want to be exposed to that and close the web page rather than continuing. it's a taboo similar to certain kinds of photographs in cultures you may be more familiar with
It's not really out of concern for people's cultures. Lots of cultures have all sorts of taboos about types of images or information. Muslim fundamentalists for instance don't like pictures of any people, of any ethnicity, alive or dead. This is just a nonsense fashion for the Australian government. All their websites have something like the one at the bottom of the page:
"The Australian War Memorial acknowledges the traditional custodians of country throughout Australia. We recognise their continuing connection to land, sea and waters. We pay our respects to elders past and present."
It makes a change from chaining aboriginals neck to neck which they kept up after I was born, along with taking babies, and having exclusion zones "boundary roads" in cities.
"The Australian War Memorial acknowledges the traditional custodians of country throughout Australia. We recognise their continuing connection to land, sea and waters. We pay our respects to elders past and present."