In Australia we own the land in perpetuity if it is sold as Freehold Land, which would account for most landsales. The government still retains the right to resume it if required and rights to minerals etc.
I think you may be thinking of Leasehold land which would generally be 99 years and is common in the ACT and for large pastoral leases.
https://www.austrade.gov.au/land-ten.../freehold-land
Back on topic, I don't agree with closing the climb at all, its a rock FFS. Culturally sensitive reasons, pffft, the usual crock of shit excuse the indigenous like to use. I get culturally sensitive when I catch them helping themselves to the contents of my car in the middle of the night. You've only got to go into any of the communities around these places to see for yourself how much respect the indigenous population have for the themselves or the land.