2023 proved untenable for dozens of Los Angeles restaurants that shut their doors forever. Some of the city’s most influential chefs closed businesses this year: Josiah Citrin, Walter and Margarita Manzke, Enrique Olvera, Zachary Pollack, “Top Chef” contestants Shirley Chung and Jackson Kalb, Timothy Hollingsworth. Caffe Roma A long-running Beverly Hills Italian restaurant closed after 45 years “with a mix …