[xjkaroom] How realistic 3D actually needed

How realistic three dimensional rendering is needed for a entertaining game?

For most games, isn't the entertainment in the mechanics and narrative?  Humans are very good at suspension of disbelief via imagination.

Portal with less fancy graphics.

But the market seems to indicate otherwise.  And movies also seem to want photorealistic 3D special effects.

One could imagine a more universal 3D rendering format / engine / API / framework with a lower barrier to entry than a modern game engine.  (And requiring less powerful hardware.) Inspired by the mostly failed VRML.