I knew Gyaban had some character evolution for Sanji!!!!
Ok, this is end game character development for Sanji. It's the final challenge I'd say.
Once again this development shows that Oda approaches character development in a very realistic way which is something I love and people often miss in One Piece. In others stories character usually learn something and get it over with, but this guy understand how we function. Evolution is not an on/off switch, it's a series of little everyday battle.
The best example is Usopp, people often believe that because Usopp learned to fight on an horrible island, therefore he should not be scared anymore, that he "evolved". But Oda knows better, far better in fact than many writers. He knows that fear and other self-destructing behaviors are deeply rooted in insecurities, traumas and memories that are not something you can just scrap out. That we need to struggle constantly to get them out.
In the case of Usopp, his fear is related to his father abandonning him. In the case of Sanji, his family rejecting him. In the case of Zoro (because despite what Gyban said, Zoro is also in an autodestruction phase) it's his grief with Kuina and a failed promisse etc.
It's really funny that even 1187 chapters later, Oda still find ways to tell us "look deeper".