They literally test it by parking children in front of it and optimising for the least amount of time spent looking away from the screen. As a result the kids get overstimulated and executive function gets damaged. Source: https://www.parents.com/news/some-think-cocomelon-is-too-stimulating-for-their-kids-we-asked-an-expert-to-weigh-insome-think-cocomelon-is-too-stimulating-for-their-kids-we-asked-an-expert-to-weigh-in/