I think Zoro and Killer were both nerfed.
Killer didn’t use his Punishers and Zoro only hat 2 swords in the beginning + Onimaru attacked him. 2 sword Zoro and Killer with scythes were pretty even.
The statement above is Oda’s way of saying that the fight in Ringo wasn’t the real deal. Both are way stronger and the fight would be more epic but the outcome would’ve been the same. So Zoro would still win.
I’m not saying this to downplay Zoro, he’s my favourite character... I’m saying this to hype up Killer. Killer is underrated