I feel like this being the first safari park in Indonesia and being built rather early in 1980 (Also due to proximity with Jakarta as mentioned), definitely are what makes it very popular and had cultural impact. Aside from the giant pandas, polar bear, and maybe also snow leopard, these animals aren't really that popular or barely well-known for ordinary guests to visit alone.
Worth noting that Batu Secret Zoo have a pair of golden takin off-display, arriving from the Czech Republic in 2021. Though, this still made Indonesia the only SEA country to held this animals in captivity.