"Viewer" is misleading-- VRML is just a file format, I expect there to
be many different browser interfaces, some immersive, some not. By the
way, people outside SGI have created immersive Inventor viewers (but
that is really orthogonal to VRML). Exactly what features would you
add to VRML to make it "really VR"?
And this mailing list has acknowledged many times that the interaction
in VRML 1.0 (moving around the scene and following hyperlinks) is a
tiny subset of the kinds of interaction that are desireable. We have
to start somewhere. Inventor is a good existence proof that
interaction CAN be added to VRML in at least one way (Inventor's
engines, manipulators and draggers are not part of VRML 1.0; they or
something like them, or some other way of doing interaction, may be
part of VRML 2.0).