"It's wild how a virtual knife in a 20-year-old shooter can have more volatile market behavior than some national currencies"

it literally not, not until latest update

its even better performing than stocks, thats why china invested millions into this

How is that wild? Currency values are controlled by governments and international market forces, virtual knives by the publisher and trading platforms. Valve can collapse the whole market with one proverbial press of a button, you'd need to be an autocrat to do that in real life and even then it wouldn't be easy.