Qantas Frequent Flyer points do not expire, as long as there is some activity on the account at least once every three years. Any type of activity at all counts, e.g. points from credit cards, hotels or car rentals (as well as the obvious earning or redeeming points from flights).
Details in the
FAQ.
"Your Frequent Flyer points will not expire provided you earn or redeem points from your Frequent Flyer membership at least once every three years. This includes earning or redeeming points with our program partners."