I was truly sorry to learn of the untimely death (aren't they all) of a friend, John Holt. In the '60s and '70s we held very similar views of the great gaps in public school education between the promises and the practices, particularly with respect to the stultifying effect of the schools on the child's ability to think creatively.
Holt's pen and voice were tremendously influential in the very limited development of alternative public school programs designed to develop independent and critical thinking in children.
The reason that parents are not interested in teaching their own children at home is that most of them perceive the shool's main function to be exactly what they would do--that is, teach their children the "basics" and discipline them. Period!
Neither the parents nor the schools are enamored of the idea that formal education has a further and much more challenging goal; not merrely to transmit the cultural heritage, but also to help develop the critical insights and creative imagination that are needed by each generation to modify that heritage to fit ever new experiences and environments. For example, today's curriculum teaches children nothing about man's responsibility in a nuclear world.