I hear these stories all the time from RAA pilots converting to GA.
The problem is this: To become CFI or HOO of a GA flying school requires a Grade 1 instructor rating and often well in excess of 1000 hours. To become a flight examiner requires even more and further training with CASA.
To become CFI of a RAA school requires around 400 hours and a PPL. CFI of RAA school automatically gets flight examiner status for the schools students.
The net result of this is widely varying standards and skills amongst RAA pilots, far far more so than GA pilots.