Sadly true -- Lear pinches technology writer's output (10)
I believe the answer is:
literature
'writer's output' is the definition.
(a writer might write literature)
'sadly true lear pinches technology' is the wordplay.
'sadly' indicates an anagram.
'pinches' means one lot of letters goes inside another (pinch can mean to steal).
'technology' becomes 'it'.
'true'+'lear'='truelear'
'truelear' is an anagram of 'lerature'.
'lerature' enclosing 'it' is 'LITERATURE'.
(Other definitions for literature that I've seen before include "writer's work" , "Written material" , "Printed matter" , "What author writes" , "Books, writing, etc" .)