[jerlam]

China, which has extremely high myopia in its student population, decided to tackle the problem top-down by reducing the amount of homework and forcing kids to play outside. They have some success: https://pmc.ncbi.nlm.nih.gov/articles/PMC9412110/

The claims have been around a long time, but how many people actually follow the guidelines? There are lots of stronger factors preventing people from doing it: economic unrest, smartphones, fear of outdoors and pollution, stronger emphasis on education, etc.

By the same token, doctors claim we can address heart disease and obesity with exercise and diet, but things don't seem to be getting any better.