This have been my dream for a long time now and it's finally coming true, I spent hours on my Xbox and always have this thought of getting paid while gaming, I've used this to create topics in the past and many said it's impossible but now I think it's becoming a reality
Technically you can already earn money while gaming for quite some time now. Selling items or accounts or earning money with twitch streaming is a thing for some years already 
Also many pay-to-win games lets you grind hours to earn otherwise paid in-game currency. What now will happen is the logical next step to make in-game items better tradeable against crypto/NFTs or fiat currency.
I still remember when Blizzard tried that in their Diablo 3 auction house. The failed back then, let's see if game comapnies learned sth in the last 10 years