The reason Oda does not come out and say anything is because people will just use it for power scaling
He did come out and say it. He made a cover of #2s, and said they were the second strongest.
He even said that Bepo isn't the official VC, just like Zoro, but is the second strongest.
Oda has also gone out of his way to label Zoro as "like a Vice Captain/First Mate", as well as called him "Captain's Shadow" just like Rayleigh in Usopp Gallery, etc, etc.
But ignore reality and fantasize whatever lets you sleep during nights, I guess?
To Oda Sanji and zoro are equals
And this is why desperate fans like you will never learn.
Oda has made Zoro and Luffy a duo
Oda has made Zoro and Sanji a duo
Oda did a Monster Trio, which exists no matter what anyone thinks.
And had, without an ounce of doubt to anyone who bothers thinking even a little on the subject, made a very clear-cut hierarchy of both power and importance among the trio, and it goes 1 > 2 > 3.
No points guessing who the third one is, it's in his name after all.