I’m not an Aussie and I’m not following this in particular, but from what I’ve seen that’s how bad ideas work: you don’t want to start a dialogue where the noes point out all the flaws in your ideas. In the US the extreme of this is legislation passed in a specially coordinated session at midnight with an absolute minimum of debate.
With that said, why the hell does a budgeted program belong in a constitution and not in a regular legislated budget? And why the hell does one specific group need specific recognition defined at the level of a constitution, as opposed to broad rules changed in such a way that their specific exclusion is forbidden with a catch all that also benefits other minorities?