Should families set shared screen-free hours rather than individual limits?

I work pediatrics, and the pattern is unmistakable: the kids who sleep badly are the kids whose whole house glows until midnight. Teenagers need eight to ten hours, and evening screen light pushes melatonin later while the group chat keeps the brain buzzing, a combination the Sleep Foundation flags as a major driver of teen sleep debt. Individual limits fail here because a kid's willpower is competing with every notification the parents are also answering. A shared household wind-down, screens off at ten, the on-call phone waiting in the kitchen, changes the environment instead of testing the child. You cannot out-discipline a slot machine. You can unplug the room.