QF doesn’t advertise PER to the east as a premium service, unlike AC and the US carriers where there are designated service levels to specific routes that are operated by certain aircraft types.

Pre covid SYD/MEL/BNE-PER were catered to the same level as AU-NZ/DPS. Despite not formally acknowledged, it’s well understood among frequent flyers and crew that the expectations were different. Other domestic flights of similar length such as PER-CBR and SYD-DRW was never special catered like these true transcon flights. For QF domestic, catering standards (catering meaning general provision of soft product, f&b being only one aspect of it) are the same otherwise regardless of flight length. There’s no published benefit to PER-east flights although in practice there were.

Now this has gone away. QF probably was looking to see if they can get away with it and pre covid just didn’t have the gut to try it. Now VA’s 330s are gone they might have thought it’s the time to test the water. Time will tell how it will turn out