Manhattan has long depended on a deceptively simple proposition: people come to the island to work, and their presence generates an enormous ecosystem around them. They commute into offices. They buy breakfast on the way to work. They meet colleagues for lunch. They stop for coffee in the afternoon. They visit shops after leaving the office. They occupy apartments, hail taxis, use public transportation, attend restaurants, visit cultural institutions, and spend money in countless businesses that depend, directly or indirectly, on the daily rhythm of office life. But what happens when that rhythm changes permanently? If working from home—or a hybrid model in which employees spend only part of the…