It was an unusually frigid December weekend when Cheng Wei summoned his inner circle to his Beijing office. The founder of Didi Global Inc., dressed entirely in black, told his lieutenants to slash spending by a fifth in 2022 and begin layoffs after staff return from Lunar New Year vacations. He delivered his bombshell flanked by a giant Powerpoint slide that read: ?Don?t live with illusions. Face reality.? ?We had a tough year,? said the reserved billionaire known as Will, who that day seemed even gloomier than normal, according to people briefed on the gathering. ?But next year will be...