When Qantas first introduced points, flying was more expensive. I flew most weeks, and I was routinely upgraded from (often discount) economy to first class. By routinely, I mean almost every time, each way. After Qantas acquired Australian, James Strong ended that, such that I could only get upgraded in one direction. I only had one international upgrade from Bus to FC for one leg, so international was different. Now, you have to buy practically any upgrade, or use a wad of points.
In the 90s, booking “reward” flights was easy. I took my wife and kids around Australia Bus Class on points - Melbourne Cairns, Darwin, Alice Springs, Uluru, Perth, back to Melbourne. All four of us were upgraded from BC to FC (they still had three classes) from Melbourne to Cairns. 4 seats, less than 150,000 points - no extra fees.
IIRC, economy between MEL-SYD was $527 I used to pay around $3.5 K for BC to LA. Since then, airline prices became much more affordable, and services were gradually downgraded. Qantas club breakfast went from fresh fruit salad with yoghurt made in-house and barista coffee to tinned fruit salad and cheap stuff, with button-pressed auto coffee machine coffee, and all other options went the same way. Flight clubs went from small rooms for a few business people to barns with hundreds of people jostling for a seat.
Airlines run on seat loadings. In the 1980s, seat prices were based on the airline being profitable at ~70% loading. You could almost always get a seat on practically any flight. Points seats effectively cost the airlines nothing, and they actually rewarded their best customers. Now, with so many people who previously could not afford to fly more than very occasionally, and deals on points with credit card providers and other vendors who pay the airlines money for them, they’ve become a form of pseudo-currency, but like Bitcoin, it’s unregulated. Caveat emptor.
They’re factored into flight load forecasts. You’ll never get a seat on a popular route at a time in high demand, because they want to collect whatever revenue they can get for those seats. You need to be creative. Pick the less popular flight times. Accept stopovers. Try the partner airlines. Accept that it’s going to be harder now than it once was.
I’m still trying to run down my Qantas points from way back in the 90s. Like @mark_m, I also lost a hefty swag of Ansett points. I’ve taken international flights on Qantas partner airlines, and when the points didn’t come through, I didn’t bother to collect them. They’re not that valuable. You have to really work hard to use them now. If you do the work, you can still get value, but don’t expect the airlines to make it easy. It’s a fallacy to assume that other airline programs will be any better. They study each other intently.
Airlines watch their forward booking loads to allocate “reward” seats, and not necessarily as far ahead as you’d think. They want to see how the booking trends are heading, and offer more generous rewards on the least valuable (to them, given the forecast sales data) seats. Their goal is to offer rewards on seats they are otherwise less likely to sell, making the cost zero, with the perceived value high.
As @Sketchergirl said, points are basically a con. The airlines show you pictures of the finest silk jackets, but deliver you the off-cuts from the fabric used to make them. You have to piece it together.
