Games have been great for decades. There have been huge hits and misses.
Games have been addictive since the beginning.
Long before UX came along to claim the credit.
I'd love to see a UX team make StarCraft. You wouldn't even get functional software.
Free to play and loot boxes are a new evolution but they are far from the only type of game.
In fact many people play fortnight and dota2 and never spend a dime.
Fortnight is popular and addictive because it's a good fun game that gets everything right for teens. The game designers and the game team did this, not UX.