In abandoning plans for a self-driving car, Apple Inc. is giving up on billions in potential revenue and the dream of selling what one executive called “the ultimate mobile device.” The hope is that other big bets — including generative AI and mixed-reality headsets — can make up the difference.Apple reached this crossroads Tuesday, when it told employees it was winding down the car project and reassigned some of the staff to its AI efforts. The decision followed months of frenzied meetings betw...