Advocate of social hierarchy in battle with big stars (9)

I believe the answer is:

feudalist

'advocate of social hierarchy' is the definition.
(someone who advocates feudalism)

'battle with big stars' is the wordplay.
'battle' becomes 'feud' (feud is a kind of battle).
'with' means one lot of letters go next to another.
'big stars' becomes 'alist' (A-list stars).
'feud'+'alist'='FEUDALIST'

'in' acts as a link.

(Another definition for feudalist that I've seen is " Supporter of old-fashioned society".)

I've seen this clue in The Guardian.

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