Not to mention that dynamic cloth isn't in Carrara yet.  And some of us find the Poser library system and posing dials, though clumsy, at least more familiar than Carrara's equivalent.  So Transposer can still be useful in certain workflows.

Oddly enough, I did a scene recently using both Transposer, Native import, and straight obj import.  Unfortunately, they all came into the scene at slightly different positions and scales.