Except for a predictable public realm, what is the difference between "Form based coding" and traditional development codes?

Practically the same. I would say that traditional development codes is a practical application of the form based coding concept to traditional neighborhood developments.

If we analyse the the forms which are being developed, they definitely get their instinct from the traditional neighborhood forms. They carry all the aesthetics, functions which traditional neighborhoods pocessed, but in little structured and modernized form. Hence, possesing the motherhood origin from them, i strongly feel, there is no much difference between them in terms of applicablility. The way they are represented and structured might have changed.