A lot of computational work yes (with the currently available hardware at least), but many visual effects are much much easier to implement with ray tracing tha

A lot of computational work yes (with the currently available hardware at least), but many visual effects are much much easier to implement with ray tracing than with rasterization techniques. Dynamic off-screen reflections, soft shadows, ambient occlusion, dynamic global illumination, caustics etc. can all be implemented more easily and realistically with ray tracing than with previous techniques.