system
A chat on subreddit /r/wallstreetbets
human
More like, they've stopped making new games, in favor of extending game life with micro transactions.   There are few new AAA games to buy, which leads to a decline in AAA game purchases.

gpt
Microtransactions are so important for revenue that every new (or old) title nowadays is designed to encourage players to buy microtransactions. But it's not fun to play a game that constantly harrasses you to buy stuff, so people lose interest in the AAA industry. 
  
 That and everyone is playing Fortnite instead. WoW and League were never as dominant as Fortnite and it's killing competing games.