He doesn't have the will to oppose and beat another conqueror such as big mom. He doesn't display desire to beat other conquerors in any form. He chose to serve others rather than rule them. Essentially, if it came down between giving up his ambition or fighting to win it all in order to save his allies, he'd do the former.
“He doesn’t have the will to oppose another conqueror”
- The entire tea party was Sanji opposing Big Mom and her plan. He even straight up blocked big mom because she was about to attack Reiju.
“He chose to serve others rather than rule them.”
- That’s like saying Zoro/Oden/Rayleigh shouldn’t be conquerors. Literally the dumbest reasoning.
“If it came down between giving up his ambition or fighting to win it all in order to save his allies, he’d do the former”
- Like Sanji wasn’t going to give up his ambition to save the SHs in Thriller Bark
- Like Sanji wasn’t going to give up his ambition to save the SHs in WCI
- Sanji regularly chooses his friends and his convictions over his life. He’s never once abandoned what’s important to him to save his life.