Historically, the boss typically has been older than the staff. But in the last few decades, several trends converged that made it more common for employees to have younger managers. One catalyst is the shift from seniority-based promotions toward those based on merit, according to a research article in the Journal of Organizational Behavior . Also, as the pace of technology innovation increases, companies promote more tech-savvy younger workers into supervisory jobs. Meanwhile, older workers are staying employed longer due to such things as the disappearance of early retirement schemes. Entrepreneur Chip Conley knows first-hand what it feels like to have a younger boss. The former hotelier works at Airbnb, where the CEO is two decades younger, as its head of global hospitality and strategy. But Conley believes that diversity of ages makes for a better workplace.…