It seems that the view interpolation paper was motivated somewhat by the lack of effective hardware for real-time rendering. They say that the scene complexity problem "is potentially unbounded" and will exist independent of the processing power of the computer. I don't know if the authors could have foreseen the advancement in graphics hardware that allows for very complex scenes to be rendered.

Here's a question:
Do you think that scene complexity is still such a big concern, and the main problem that needs to be dealt with?