Just because the Zoro fans were flying too high recently with all that "ZKK" stuff, black blade etc. So Oda just wanted to give them a big L.Oh my bad
on that note, can you tell me what Oda thought he was doing with Zoro this arc?
like does he think he did Zoro well with this kinda mid final fight, no character development
Don't worry, next arc Zoro will have a insane fight.