> few people use it. How many pages have you looked at that the designer used 
> ECMAScript?

Almost every commercial web page uses ECMAScript.  ECMAScript is essentially
an attempt to produce a tight specification of those parts of Netscape
Javascript that are general programming language features, i.e. excluding
everything to do with the document object model and everything to do with
browser automation.  You need the object models in order to do anything useful
in a browser.

This makes me think that you don't actually understand the concepts of
scripting languages and object models in relation to HTML and web browsers.

> To allow people to create or structure their own languages by a Scripting 
> DTD, would give

Meta syntaxes for programming languages are almost as old as programming
languages, e.g. Backus Naur Form.