If it was the case, Oda would not have created the supernova and worse generation system to seperate Luffy and Zoro from Sanji, as well as calling Zoro vice-captain by a fellow supernova(Urouge) and a strawhat fanboy(Bartolomeo), would not have given Luffy and Zoro better trainings and so on. When will people finally acknowledge Zoro is the stronger of the two? No one is saying Zoro will roflstomp him, but Sanji is clearly weaker. Zoro will win after a high diff fight
That's....exactly what he said. Third strongest, and a bit weaker than Zoro, aka, a high diff fight. Why did you get so defensive?
BTW, bounties don't accurately reflect strength like that, unless you wanna say Doffy is weaker than Luffy and Law.
Also, there has also been cases where people thought Zoro was the captain. That shows outside opinion of the crew isn't always right, so just because Urouge called him first mate, doesn't mean he's first mate. The WG, who are more knowledgable than Urouge, call Chopper their pet. I suppose he's not really their doctor then.
But I genuinely don't recall Barto calling Zoro the first mate/vice-captain, could you show me a scan of this please?
Besides, first mate is whoever will take charge should something happen to Luffy, which Luffy has declared to be Usopp actually. Usopp being vice-captain is actually more canon than anyone else being vice-captain xD
And I honestly don't see Luffy having a ranking order like that. We've seen different people have a voice of authority before, Sanji has authority over the crewmembers he was with against Big Mom. Zoro had a voice of authority when it came to the incident with Usopp, where everyone agreed not to take him back unless he apologized. The Strawhats seem to have a system where Luffy is number one authority, and the rest are equal. I don't think Luffy is the type to have a "first mate" per se.