Play is not frivolous but is an adaptation designed to guide proper cognitive development in human children.
The current anti-vaccination movement is a result, in part, of the innate cognitive biases inherent in our nervous systems that evolved to deal with problems in a very different premodern world.
Introducing germicidal blue light essentially creates a new environment that most bacteria appear to be mismatched to survive within. But we may be mismatched as well.
Cultural evolution created technologically-advanced contexts that make it difficult for doctors to communicate with patients in manners concordant with our evolved, ancestrally-familiar modes of communication.
We haven’t evolved to be successful in the modern world.
Our drive to exceed our evolutionary limits sets us apart from other beasts