This is understandably a gray area, and a matter of debate. But "tyrants" is certainly not the right word. I cannot speak for this individual case, but in many countries it's forbidden to damage, sell, tear down protected buildings and areas, because they are classified as cultural heritage. In some case it's a crime under international law to destroy cultural heritage even in war. This is just to say that it's perfectly normal to forbid the selling out of certain lands or artifacts, if in the public interest.
If Aboriginals have land rights on the basis that they lived there for thousands of years, and are then restricted from changing anything that has thousands of years of history, what have they actually been given? It sounds like a sham ownership of the land.
They are totally ordinary people. They should have the right - indeed the expectation - to change their surroundings in ways that are to their material benefit. The fact that they lived there for thousands of years can't be the starting point of an argument that they have to sit there living with pre-1900s style infrastructure and no money.