Heres a little anecdote that I'm sure I share with at least a few.
Year was 2017 or 18. Can't remember. Was when I finally shelled out for a Gaming PC. Saw this game and saw the playerbase,
the future seemed bright for the game. I never bought anything for any games I've ever played but KF2 always put a twinkle in my eye such that I decided to make it the one game I would buy "whatever I thought I might want" in terms of cosmetics and such.
So I began procuring a myriad of items that made me feel further immersed in this experience, while corny at best the squad based gameplay allured me, as did the gunplay. From my perspective at the time it seemed KF2 would live a long life like how TF2 is still mainstream today...
Eventually it became an obsession, to collect items of similarity. Gas masks, helmets, facemasks, mostly.
A handful were in very high demand at the time, and consequently cost a pretty penny. I had money to burn at the time, so I figured "I'd rather have that than the money" and bought it anyway from the market.
An example would be the German Gas Mask. I payed about 10 dollars for it, it was a rare item only 10 for sale in the world. Thinking the value would rise, I snagged it at the first opportunity. And eventually it did. Rose to about 15 dollars, in a few months. But I didn't sell it. THEN Tripwire added it to the in-game store for a price of $7.99.
At the time of writing its currently going for less than 6 dollars and dropping. But thats only one of the more opportunistic items that still hold SOME value.
Another one is a type of helmet, payed 5 dollars for it thought I was getting a bargain because everyone else up the line was selling for $12 and up.
Long story short that helmet today is available for about 55 cents.
Most of those items are now worth less than a few dollars, and rapidly declining with the further declining playerbase, and a subsequently crashing market.
KF2's market was always ridiculous, prices bouncing like someone was reading them off a BINGO card, but they've never sunk this low to my knowledge. I'm sure someone will prove me wrong.
It was the Gary Busey christmas event. Everything seemed fine, everything was "going to plan" albeit some rumors that paid weapons were coming. I didn't think much of it considering a USB key to open a loot crate cost about $2.49, an entire outfit costing 4.99 they couldn't possibly want much for a gun....
Then we got a few "Quality of life" updates the next spring, that "fixed" a lot of things no one complained about until they changed them ---- subtle hinting that things kinda losing direction among the brass.
Then one faithful halloween the following year, Grim Treatments dropped and Tripwire decided they would kill their golden goose and turn it into a cash cow instead. And by cash cow I don't mean sensibly as in a reasonable price with a quick turnover from mass purchases; they went 10 dollars for a single gun, whereas they'd only get a few bites and the rest of the community immediately shunned the devs in outrage.
It seems clear to assume that the money they get is going to developing the payware, whilst implementing readily-available community-made content in place of "new free content."
Updates continued to decline the quality of the game, especially the introduction of HRG weapons that are literally retextures of existing weapons coded to function differently, while the real new stuff has a price tag of 10 dollars. Each. I could care less at first about the weapon DLC, as it was something I could avoid, as the weapons didn't really outclass much already implemented; but these HRG weapons were just a middle finger in the face of "New content," marketted as if these things were being unveiled as premium quality free content, judging from the overly dramatic introductions of the main menu animated background.
But I digress, tremendously.
Item values dropped as less people wanted to buy things.
Back when I bought a majority of the things I did, I did so in the face of "I could always resell it"
but not anymore.
Frankly, it would cost me more to sell the items than to keep them.
And as such it would be a waste to just quit the game after all that;
It would cost me more to stop playing KF2 than it would be to break free.