I wish I could up rep you more A V I!
You're saying it's been portrayed for 10 years pre time skip that they are rivals and are on par with each other, yet Zoro always fought the second strongest?
As for FI,
You must be registered for see links
, I guess an enemy who Luffy considers strong and looks like he's excited to see has strength is just fodder... He was fodder for Zoro I guess, but he was fare greater than any opponent in FI bar Hordy, so once again second strongest.
Vergo was stronger than Monet, but don't forget, she very nearly took out Luffy, she was far from fodder, but still isn't a representation of strength between the two.
And Dressrosa, Pica was described at the top/strongest executive, once again being the second strongest... Sanji did have bad match ups after FI but if anything it does show that he's leagues below Vergo and Doffy even if they were just skirmishes, but that's exactly what Zoro had with Fuji and contended with him well.
Zoro is stronger than Sanji, this has been shown throughout One Piece.
I was going to comment with my own opinions, but I got half way through your list and thought how ridiculous the ranking was, followed by ridiculous rankings in further comments so I won't bother.
EDIT: The title of the chapter is actually "Highest Executive Pica"... fodder though right?