Absolutely not. He began the flanderisation of the Strawhats well before the others- before Brook and Jinbei had even been introduced- when in EL and TB him being an attempted ladies man suddenly went into overdrive and he became a raging simp sex pest.
From the Saobody Split up until Zou he was an actual joke. Like, Oda was genuinely treating him like trash for no reason. He got the joke training, he got the joke treatment in FI, Oda had him break his leg against what is basically a totally unimportant villain like Vergo then he couldn’t even get a cool moment saving the crew without Law stealing his spotlight.
Then came Zou and Germa. I can only assume that during the two odd years that Sanji was absent in Dressrosa that Oda came up with this as a last ditch attempt to remedy the complaints about Sanji. In my opinion, he failed woefully.
After twenty odd years Sanji’s character suddenly revolved around his kindness. Sanji is, apparently, the kindest man people have ever met. Where the actual fuck did this come from? Yes, he was capable of kindness, but so is Zoro and every other Strawhat. If kindness was meant to be a defintive feature of any Strawhat I would have chosen Chopper, not Sanji.
His entire familial background came from nowhere and was a trite attempt to recapture vastly more successful stories like Nami, Robin and Law’s. Not a single interesting character was introduced as part of Germa. It did not a single intetesting thing for Sanji’s character, all it did was turn him into a crying, snivelling moron. Oda, for some bizarre reason, refused to even give Sanji much of a success at the end of the arc. Sanji ultimately needing to be saved by Germa? That’s the payoff for an eighty chapter arc about how Germa think he is a weak minded failure?
Then comes Wano. “I am never going to use the RS!”
Immediately uses the RS
“Does Luffy want a chef or an emotionless super soldier?”
What the fuck do you think, he literally told you not an arc ago that he wanted you as a chef.
Then of course there was no actual downside to wearing the RS. No emotions lost or anything, just awakening yet another powerup that comes from Judge. And this is supposed to be great character work?
No, Sanji was a great character when Oda kept things basic with him up to EL. Bad tempered cook with a soft side who turns into a bit of a fool around woman. Can come in clutch with moments where he stops to think and plan ahead. It wasn’t anything elaborate, but it worked and he was likeable. Oda took all these aspects and turned them up to 11, making him a mess. Now he’s totally deranged around woman, is so passionate he’s basically a frothing at the mouth mess at times, yet is apparently also a human saint. Also Oda’s dumped the clutch moments which were so cool.
TL;DR. Sanji has been a mess for decades and is as clear an example of more not being better than you‘ll ever see. The character peaked on the train to EL and it‘s been a schizophrenic downward spiral ever since. Oda tried to fix it but only made things worse by throwing in the terrible Germa plot.