Colorful seats and USB ports aren’t enough to attract younger passengers. Upholstered with brightly colored fabrics, the seats on Joon, Air France’s millennial-targeted airline, look especially chic. Flight attendants wear white sneakers, jeans, and blue polos — what the airline calls “smart casual attire.” Download the airline’s app, YouJoon, before your flight and you’ll get access to channels like Viceland and Red Bull TV on your personal device. “The new generation of travel experience by Air France” is their tagline. And they are failing.