What are you basing that on? There is evidence that not teaching children to read until age 6 or 7 has an overall net benefit.
Many countries ranked very well for education, don't start formal education until age 7 (Finland and Sweden for instance). The children in these countries are taught to read later than in the US, but they do just as well or better on reading tests later in life.
Children in the US weren't taught to read until first grade a few generations ago. Hell, when I was in kindergarten, 25 years ago, we spent the whole year learning the alphabet--now kids are expected to know the alphabet by the time they enter kindergarten. There is no evidence that this is beneficial and plenty that it is harmful.
Many countries ranked very well for education, don't start formal education until age 7 (Finland and Sweden for instance). The children in these countries are taught to read later than in the US, but they do just as well or better on reading tests later in life.
Children in the US weren't taught to read until first grade a few generations ago. Hell, when I was in kindergarten, 25 years ago, we spent the whole year learning the alphabet--now kids are expected to know the alphabet by the time they enter kindergarten. There is no evidence that this is beneficial and plenty that it is harmful.