The author, like many well-intentioned liberals, makes the mistake that children think exactly like miniature adults.
These are 5 year olds. They do not see race as important. This is good. When they grow up, my sincere hope is that it won’t be.
Furthermore, many of the ideas involved in raising children to be “anti-racist” are complex concepts that young children are developmentally not capable of understanding. There will be a time and place for all of this, but at this age, children need to understand that we really are far more alike than different and that racial differences are literally only skin deep.