A decade ago I was an intern at Google. One of my mentors said something that has stuck with me: "Google found a hose that money pours out of and it's name is online advertising. All we do now is desperately try to find another hose."
Google's strategy for a long time was: Hire every clever person you can; give them some creative freedom; see if any of them come up with a trillion dollar idea.
Only now they've 'grown up'. 20% time is dead. There is no second hose. They've mostly given up on the idea of a clever person finding a new money-hose. They just focus on the one they have now.