tubs the sea saver
30-40 years ago, I remember reading the catch reports from the shore based competitions, and how the bulk of the catch consisted of edibles in the early days, and then later it changed to in-eds, particularly young dusky sharks (ridge back greys). The duskys made up more than 90% of the competition catches in the 80s. I'm not sure if that is still true, but the theory at the time was that the inshore shark netting culled the large sharks and allowed the grays to breed in an inshore safe haven.
I believe that this is the issue, the larger sharks that would normally keep the smaller ones in check have been removed from the system thus allowing the smaller and medium sharks to become a plague. Human interference caused the issued in the first place.