Niche product ultimately diverted folk (6)
I believe the answer is:
ethnic
'folk' is the definition.
'niche product ultimately diverted' is the wordplay.
'ultimately' suggests the final letters.
'diverted' is an anagram indicator (each letter get diverted elsewhere).
The final letter of 'product' is 't'.
'niche'+'t'='nichet'
'nichet' with letters rearranged gives 'ETHNIC'.
(Other definitions for ethnic that I've seen before include "Relating to cultural divisions" , "Relating to a particular racial group" , "Having a common race or cultural tradition" , "Relating to cultural groups" , "Characteristic of a certain culture" .)