https://onepiecechapters.com/chapters/76/one-piece-chapter-1006
Reread chapter 1006 and stop arguieng with me since you clearly don't know what you're talking about.
When they thought Marco was defeated in chapter 1022, he was in fact not defeated and jumped in to block King's attack in the very same chapter.
Then he was simply tired of fighting and chose to give the stage to Zoro and Sanji (Cause they are the main characters).
Sanji would be lucky to end the series on Marco level but i do believe that he will be at least somewhere around the level of a YC1.
Sanji will never be as strong as an admiral, period.
Thinking Sanji will be on the level of an admiral is absolutely delusional, it is as delusional as thinking Admirals = Yonko Commanders.