I dare say 99% of PPL/CPL folk who do not travel there daily would not even realise it exists.
Possibly so, but with an ounce of responsible and professional conduct as pilots, if & when they do have the need to go there they will look @ their charts, ERSA FAC YPPD - perhaps even NOTAM and WX - and educate themselves, same as we all should do when going to any unfamiliar area/location.
Those who do fly in the region should know about it. There was extensive education @ RAPAC & via the various industry associations.
Try dropping into KA or BRM and claim you didn't realise CTA & a TWR existed -