Well, if they used a textureless polygonal engine it would have the same problems as the rest of the 3D games in the platform - "framerate choppy, controls are terrible, why bother with 3D when with 2D would be much better", etc. They rightfully sticked with a birds' eye view, altough a side scroller à là Prince of Persia would be an even better choice.
Now, this one, from what I remember , t'was an average title back when first released. Now it's an aged average title.