With the great risk of betting on something new, large publishers prefer to focus on known IPs.
As Spencer wrote in his leaked email (via Kotaku), "If you were a studio, you needed a AAA publisher to reach a customer at an Egghead Software."
In the era of digital distribution, however, access to physical distribution channels is no longer required. That's led big publishers to lean on their other strength: Making big-budget blockbusters that are out of the reach of smaller operations.
"Very few companies can afford to spend the $200M an Activision or Take-Two spend to put a title like Call of Duty or Red Dead Redemption on the shelf," Spencer wrote. "These AAA publishers have, mostly, used this production scale to keep their top franchises in the top selling games each year."
"AAA publishers are milking their top franchises but struggling to refill their portfolio of hit franchises—most AAA publishers are riding the success of franchises created 10+ years ago."
The point of Spencer's email was to emphasize his belief that as major publishers find their footing eroded, subscription services like Xbox Game Pass offer them a lifeline. He noted that EA and Ubisoft were both trying to build their own competing services but said "they are not moving quickly or boldly enough to scale," and also suffer from the lack of a platform like the Xbox console to launch with. Spencer said he wasn't looking to kill off the big publishers with Game Pass, though, but to help them "build towards a successful future" by giving them access to a massive user base that they can monetize as they see fit.