Oh, my friend, you have no idea how far Oda's maniacal love for Zoro goes. It's not the first time that Oda makes Zoro look better than Luffy... do you remember Alabasta arc? In Alabasta arc both Luffy and Zoro were facing the same problem in their fights: they couldn't damage their opponents because of their DF abilities; Crocodile had a logia type DF and Luffy couldn't physically touch him, while Doz Bonse had iron based DF and Zoro couldn't physically cut it. Now, look what happened there and how they dealt with those problems
Luffy used water to counter Croc's abilities while Zoro awakened haki, but no just CoA haki; no, no, no... Zoro awakened both CoA and CoO haki at the same time. Zoro was the first strowhat to ever awaken haki, Luffy managed to do that only after Thriller Bark when he first used CoC against the bull. But it doesn't end there, in Wano we find out that the haki that Zoro awakened to cut iron in Alabasta is the same haki that Luffy was trying to learn in Udon "Ryou",
of course Luffy ended up learning even the stronger version of that haki "Internal destruction" but it doesn't change the fact that Zoro did it in fu*king Alabasta. Also, in whiskey peak Oda portrayed both Luffy and Zoro equal in strength
Any other outher wouldn't hesitate to show the difference between Luffy and Zoro, at the end of the day Luffy's dream is way harder to achieve than Zoro's dream (it was said by Mihawk himself in barati arc), so there's no problem to show that Luffy is stronger than Zoro especially when Zoro is just a supportive character and has nothing to do with the main story about Pairets. But no, Oda couldn't possibly do that to his favorite character that he loves so much, as matter of fact, he later confirmed it in Datebooks...
Oda also portrayed Luffy and Zoro somewhat equally in Blackbeard scene.
There are also small things like; people mistaking Zoro as the captain of the crew or being surprised that Zoro isn't the captain of the crew etc... but when Oda is forced to choose someone between Luffy and Zoro he will always choose Zoro over Luffy, we are seeing it here in the fight against Kaido. This fight has been labeled as "the battle for the PK throne" and amongst all characters who could have been the main fighting force of this battle Oda chose Zoro. Why, why him? Zoro has nothing to do with PK dream, he has never even shown any interest for that title, but Oda chose him completely ignoring and ruining Luffy's character for sake of his treasured Zoro. I'm the only one who is talking about it, no one amongst one piece fans or hypocrite one piece Youtubers have said anything about it. Nobody gives a s*it that Oda has completely ruined Luffy's character by putting Zoro in fight that he shouldn't have been part of in first place. Zoro has his own dream–his own plot line, Zoro should have fought against King (a powerful swordsmen) but Oda couldn't possibly show the difference between Luffy and Zoro. For Oda Zoro is too strong for mere YC1 "Kaido's right hand man" Zoro instead should fight against Kaido and
overshadow Luffy. Luffy and Zoro are the only ones who can damage Kaido while Luffy's direct rival–Kid and Law are absolutely useless outside of taking orders from Zoro and Luffy and covering their asses. Luffy fought against: Doffy, Cracker, Katakuri, Big Mom, Kaido and in result of it he awakened FS and later on he traind in Udon and awakened "Internal destruction" haki, but Zoro, fu*king Zoro surpassed Luffy with just one power up while never being pushed to his limits, he still hasn't gone all out yet. Can you imagine that? Oda is an absolute lunatic when it comes to Zoro, he probobly kisses Zoro's pictures every time he goes to sleep. How far will Oda go with his maniacal love for Zoro is yet to be seen, but one thing is certain, there's nothing good will come out of it.
He even married his wife who ironically cosplayed Nami.