Most modern day sophisticated aircraft now have very accurate FF's & Qty's known at anytime whilst enroute.
Sure. For those aircraft you would have a fair idea of whether you were burning your VR, or not. But still many hundreds of commercial aircraft in Australian skies where the pilot wouldn't know.
But, regardless of how sophisticated the aircraft, there still remains the high likelihood that VR is being burned on any given flight, and with only a small amount of VR to start with, the chances are very good that, if departed with minimum fuel, the fixed reserve will be eaten into - necessitating a diversion or mayday call.
... there should be no change to what was happening the day before this was implemented ...
The day before, an operator could depart on minimum fuel with the chances of getting into fixed reserve considerably lower - because he had 10% or 15% VR. Now, the turbine aircraft can legally depart with zero or 5% VR, with none at all for any diversion to an alternate!