The answer is not straightforward. We believe it could be. Depending on which origin story you assign to.
Genetical analysis have shown that ABC is the most distant relative in the Cannabis Genus even further than Hemp. This could be an indicator of long genetical isolation and adaptation to the Australian environment. There is the possibility that the Polynesians or Aborigines, as many human settlers, brought Cannabis with them and it became feral in Australia and was later on rediscovered by the descendants of the European settlers. In this case if the Natives undertook any form of selection process, ABC technically could be a Landrace, which later on became feral.
The other origin story is that ABC became feral from Hemp populations that the European settlers brought with them. And due to the extreme conditions of the Australian climate mutated heavily and survived the Cannabis eradication efforts of the Australian Government, thanks to the stealth appearance. While not impossible, we believe this story to be less likely, as ABC is THC dominant cultivar, with barely any CBD or resemblance of Hemp cultivars. Moreover, does the original aroma profile of ABC resemble the one typically found in Sativas.