Just throwing stuff at the wall here, but with the coming population collapse, I'm thinking we might be able to derive some lessons or maybe even a blueprint for how to navigate said collapse by examining MMORPG economies. I know that in the past economists have studied WoW in earnest so maybe there's still some insights yet to be mined.
How does the economy change once the server population starts shrinking?
I know from my own experience playing FFXI back in the early 2010s that there were regularly specialized materials on the auction house that wouldn't get stocked regularly. In my case it was some fish and for a couple weeks I was able to make good money at it because while there was almost no one supplying the item there was definitely still a demand for it. Then someone started flooding the market and I moved on to other ventures. No idea if the end result of that was a temporary supply or if it turned into a stable availability of the product. Maybe the one guy just made a whole bunch of product the one time and then once it was sold he moved on to the next thing and all the smaller producers like me ended up gone and the product itself just outright vanished from the market.
I imagine the dynamic is quite different now as the population dwindles further, although they do consolidate servers so that might throw a wrench in the fact finding opportunities here.
So, mmo arent a great allegory for real world economies because there isn't need in a virtual world, but we can gain some basic ideas that might resonate with people who have experienced them but might not be able to correlate those experiences with the real world in their mind.
Supply vs demand is the basis of all economy. Your fish werent being supplied, and demand was high so price was good. Others saw this and flooded the market to try and gain some of those high profits, then decreasing demand(more people fishing them) and increasing supply, driving the value down, eventually driving "gold rushers" out of the industry and stabilizing to the new price based on fulfilling the finite demand, with price based on the effort to produce the good. This is a stable economy.
This is how a need based economy works too. It takes land, time, skill, and labor to produce food. If food is rare, its price will be high. If land is rare, its price will be high. Etc.
When price is high, people will see the profitability and produce it in abundance, then driving the price down and eventually normalizing. This is disrupted if you do not have either a truly free market, allowing for direct competition, or a captured market(i.e. guilds) who need to maintain proper supply demand stability to ensure continued prosperity for the producers. Guilds work VERY WELL for sustenance production, while free markets work better for luxury markets. The reason is that if sustenance production crashes, people die. A guild market fluctuates less, and also hinders new additions to production, ensuring a continued desire for production.
This is another huge hole in the MMO economy that does not make a good analogy for the real world:
Fish rots.
You can't just have an over abundance of things lying around to dump on the market when demand suddenly rises. People would have thrown out their excess fish a LONG time ago.
An entire, massive segment of the economy is the economy of scale and shipping things in a timely fashion before the goods go bad. None of this is represented in any MMO economy that I am aware of.
What they DO represent well, however, is Fiat currency and inflation when more currency is simply dumped into the economy with each new update.
You make an excellent point, which goes into the balance of value. If you want something you cant make locally it costs more. If its perishable the market pressures determine what you make so it doesnt spoil, but it also requires continued effort, increasing cost.