I don’t think she was a commoner. She was raised to marry his brother Andrew.
Technically she was but more of an uncommon commoner since her daddy was a nobleman.
https://www.biography.com/royalty/was-princess-diana-a-commoner-before-marrying-prince-charles
https://www.biography.com/royalty/was-princess-diana-a-commoner-before-marrying-prince-charles
She was probably too old for Andrew. Lol..
“I don’t think she was a commoner”
No she was Lady Diana Spencer, daughter to the Earl of Spencer. Her bloodlines were bluer than Charles.