But we don't need to.
HTML is a perfect example of a standard that isn't perfect
for everything, but does 90% of what 90% of the people using
it want to do-- it is good enough. And it is flexible
enough that you can usually find a workaround to do what you
want to do (like imbed an image of your formatted equations
since it doesn't support equations, or whatever).
I think VRML can be at least as useful and flexible for
3D stuff as HTML is for 2D text, without an API or
scripting language.