Here is what the current rule says:
234 Fuel requirements
(1) The pilot in command of an aircraft must not commence a flight within Australian territory, or to or from Australian territory, if he or she has not taken reasonable steps to ensure that the aircraft carries sufficient fuel and oil to enable the proposed flight to be undertaken in safety.
Penalty: 50 penalty units.
...
(3) For the purposes of these Regulations, in determining whether fuel and oil carried on an aircraft in respect of a particular flight was sufficient within the meaning of subregulations (1) and (2), a court must, in addition to any other matters, take into account the following matters:
(a) the distance to be travelled by the aircraft on the flight to reach the proposed destination;
(b) the meteorological conditions in which the aircraft is, or may be required, to fly;
(c) the possibility of:
(i) a forced diversion to an alternative aerodrome; and
(ii) a delay pending landing clearance; and
(iii) air traffic control re‑routing the flight after commencement of the flight; and
(iv) a loss of pressurisation in the aircraft; and
(v) where the aircraft is a multi‑engined aircraft—an engine failure;
(d) any guidelines issued from time to time by CASA for the purposes of this regulation.
(4) An offence against subregulation (1) or (2) is an offence of strict liability.
Note: For strict liability, see section 6.1 of the Criminal Code.
What is the safety risk created by this provision, the mitigation of which is the provisions of Part 91, and how, precisely, is that mitigation going to be achieved as a matter of practicality?
If there are no coherent answers to those questions, it's a completely pointless (and wasteful) exercise.