Yes, protected. Becoming PC ? Well I dunno, the Act is a 1974 Act. I dunno when Part 6 was put in place.
If you felt you had a good reason to destroy one you can go down a legislative and consultation road to get that approval. If you think protection of Aboriginal items is 'too PC' you'd have a right panic at the consultative requirements.
Personally I think the biggest philosophical issue with the current legislative protection of Aboriginal heritage is it's inclusion with the birds and bees and national parks, rather than as part of a dedicated heritage legislative regime (like whitefellas have in the Heritage Act 1977).