No, it is not recommended to let a 2-year-old watch TV. According to the American Academy of Pediatrics, children under two should not be exposed to any screen time at all. This includes television, computers, tablets, and smartphones. The AAP recommends that parents instead engage in activities with their young children, such as reading books or playing together outside. These activities are more beneficial for a child's development than watching TV and can help foster healthy habits early on in life.