Discussion of the "Good Old Days" is all well and good but you're also talking about routes that probably lost a fair amount of $$$ too.
While QF has an obligation, of sorts, as the main flag carrier to service most of Australia, and it does pretty well regionally, these days there are commercial realities. We all have our personal "pet" routes we'd like or do like or want back, but it's not all about us as individuals it's about what actually works. QF clearly feels, for example, they can't make money flying a widebody (eg: 330) to SIN from PER, but a 737 is a good size fit. As pax we don't like it, specially in J and I *totally* understand that and feel that pain, but the reality is they are competing against a mega carrier to their hub (SQ) where QF has (now) little onwards feed on their own metal, it's basically all ceeded to 3K and if you're a Y pax, flying a 737 PER-SIN and connecting to I don't know HKT or CGK or something on a 320 is going to be roughly the same experience. J is a different issue totally absolutely, but this is a commercial decision.
QF like most other legacy carriers operates a hub and spoke system. Like it or not, QF's main hub is SYD, with secondary hubs at MEL and to a lesser extent BNE. The comments about SA flying to JNB are hey guess what... SA has a hub at JNB and feed from there. SQ to SIN? CX to HKG? TG to BKK? all hubs on the end. This is what alliances were built for... route those pax on your partners where you can't serve it yourself.
If PER were a population centre the size of MEL this wouldn't be an issue, but PER is small and isolated. Just can't make money on many routes in competition with these other carriers who can fly those widebody a/c to/from their hubs at a lower cost specially when you have partners who can take your pax even if it is over a few more hours (eg: CX/MH/EK).
If you're a VA pax and you want to get to Hong Kong you face a similar dilemma that you'd have to go on SQ via SIN and the shoe is on the other foot.
Speaking of VA, what do they offer the Australian based pax out of PER? Zero bar codeshares on NZ to AKL and SQ to SIN and probably EY to AUH (I am not certain if EY serve PER off the top of my head). If you ask me you're just as hosed, if not more, ex-PER by VA than you are by QF.
Fact is we're a huge country with only a couple of large population centres, which are within a few flight hours of each other on the east. That's where the demand is. I'm sorry PER but if it wasn't for the resources and so on you'd be treated probably like ADL, maybe a little worse. No offence intended - I love PER it's a lovely place but on a world scale it's too far away and too small relatively to provide the demand to make these things work.
Unless you want QF to serve all kinds of whacky places from places like ADL/DRW/PER/CNS and lose $$$ and go out of business....