Doesn't that mean there's good smooth jazz?
There are some Smooth Jazz albums that fit rather better into the tradition of Soul Jazz than others. Try Urban Knights for that - of course, Ramsey Lewis does make a dfference. In general, Smooth Jazz suffers from exactly the same defects as Smooth Soul - some talented musicians and singers, but not much soul, not much conviction, no real story to tell. They probably wouldn't be ALLOWED by their labels to tell their story anyway.
MG
Well, it was a rhetorical question intended to show that saying that particular categories of music have good stuff just hides the aesthetic judgement in the choice of category. (With reference to AllenLowe's example: if he doesn't think any smooth jazz is good the argument now hinges on the placing of smooth jazz in the jazz category.)