Not necessarily. The DEC's, I believe, were employed on temporary contracts through an agency that were unavailable to current employees.
It was a kind of stop gap measure supposedly for a number of months, due to a short term captain shortage, but they transferred on to full time contracts at the end of the initial contract period.
There were plenty of experienced FOs ready for command but the company weren't prepare to promote them on the basis of a temporary requirement.
I was one of the FOs ready and waiting.
Not saying I agree with it or the situation down under just that it happens everywhere, always has and always will.