Sadly so. It's pretty sad when usage and demand keeps going up*, with mountain biking in Australia is booming generally - but the club is blocked from doing repairs/upgrades, toilets aren't repaired, roads and carparks are badly eroded, etc... As I understand it the club isn't even asking for funding for trails and are willing to wear the upgrade/repair costs themselves as long as permission for the works is granted. But currently it's a all just a big "no" under the blanket "culturally significant" refusal even though the trails are already existing and see huge usage/demand.
*(Seemingly even over winter, with Stockyards carpark full to overflowing a couple of times even on non-shuttle/event weekends this year)