I suspect it was focussed on International.
Same with the Qantas Domestic Business lounges (SYD, MEL, BNE, PER, CBR) which are limited to Business, oneworld Emerald, connecting First/Business (or EK or MU Plat)
The other interesting one is the HKG The Arrival lounge which is available to OWE in any class, but only when arriving on CX/KA