Second theatrical award includes concerning lack of diversity (8)
I believe the answer is:
monotony
'lack of diversity' is the definition.
(monotony means sameness or a lack of variety)
'second theatrical award includes concerning' is the wordplay.
'second' becomes 'mo' (both are short periods of time).
'theatrical award' becomes 'tony' (Tony Awards).
'includes' means one lot of letters goes inside another.
'concerning' becomes 'on' (both can mean 'in relation to').
'mo'+'tony'='motony'
'motony' going around 'on' is 'MONOTONY'.
(Other definitions for monotony that I've seen before include "Tedious lack of variety" , "It's wearisome" , "Sameness" , "Unvarying tedium" , "fixed routine" .)