Or, Oda used Sanji to hype up other characters because as long as Sanji succeeds in protecting other peoples lives he still accomplishes his goal?
Punk Hazard - Saves Tashigi and the G5 marines and carries them to safety after the fight
Dressrosa - Succeeds in saving Brook Nami Chopper and Momo from Doffy then again against Big Moms flagship.
WCI -Wipes the floor with Yonji for insulting those important to him. Forces Judge (a yonkou commander level fighter) to cheat in a one on one duel, and breaks through the exoskeleton of Niji with a single kick, then kicks oven so fast he saves Chiffon and carries her away without anyone noticing his presence.
Wano - Fights Page One, a Tobi Roppo, until everyone is safe then stops because he didn’t wanna cause unnecessary damage to the capital and the plan. Fights Drake, another Tobi Roppo, low diffs him in the anime and even in the manga was able to win or escape unscathed, then defeats a 1.3 billion berry commander in Queen.
But no Oda doesn’t plan on him being a fighter.