ON A CRISP fall day in 2019, John Lutz departed the writers’ room at “Late Night with Seth Meyers” for a two-week television shoot. On the way out, Lutz’s office neighbor, Mike Karnell, jokingly asked whether he could eat lunch at Lutz’s desk while he was away. Lutz ignored the wisecrack and warned, with apparent sincerity, “Do not eat lunch at my desk.”