I'm not advocating, I'm explaining why it already happened twenty years ago. Polygons can be trivially subdivided to a rounded surface or converted to a subdivision surface. This is something anyone who has used maya, houdini, lightwave, softimage or 3D studio has seen their entire career.
If you think using polygons solves no problems, I'm guessing you haven't tried to make a pipeline with nurbs (not many have in this day and age). Texturing takes specific paint and texturing tools while the resolution difference between patches complicates things even further. Even getting the model detail is difficult. Everything about it is painful. It isn't even a contest, everyone transitioned to polygons and no one looked back.
If you think using polygons solves no problems, I'm guessing you haven't tried to make a pipeline with nurbs (not many have in this day and age). Texturing takes specific paint and texturing tools while the resolution difference between patches complicates things even further. Even getting the model detail is difficult. Everything about it is painful. It isn't even a contest, everyone transitioned to polygons and no one looked back.