Aboriginal Australians were literally stone age people when the white man arrived. They never smelted any ore, despite Australia being one of the most ore rich countries in the world. So they did not get as far as a Bronze Age, nor Iron Age. They also never invented the wheel, or the bow and arrow. They also never developed any civilisations (look up the definition of civilisation). They were tribal stone age people, and those tribes were often at war with each other.

Today there are very few full blooded Aboriginal Australians. Most people who identify as Aboriginal have a lot of European blood in them, and are typically about 1/4 or 1/16 Aboriginal. For some reason those people generally do poorly at school and have high incarceration rates.

Are they generally less intelligent? Well of course it depends on your definition of intelligence. We are not allowed to answer yes to this question, it is illegal to say yes, that would be racist.