Sundar seems very confused here. The idea that we should invent AGI to make "personal digital assistants" is like Hogwarts students inventing time machines so they can take two classes at once. I mean, yes, it would technically enable you to do that, but it doesn't matter because at that point you have way, way bigger problems. If a fleet of alien spaceships arrived in the sky over Manhattan tomorrow, our first react…
By the time AGI is developed, it would be able to improve itself/build improvements, causing the runway effect that leads to superintelligence. The idea of making "personal digital assistants" is humans thinking they can tame a god to be a servant. Taming a superintelligence would be like a dog taming human civilization, and perhaps the gap between man and ASI is larger than the gap between dog and man.
I see no reason that's necessarily true. I'm a general intelligence, and I can't make myself smarter.