Exactly, Oda doesn't think like that, he just follows the linear path of the journey which leads to the simple ''Zoro+new sword= Stronger Zoro''.
Except then Oda adds complications
Oda has Zoro struggling to use Sandai Kitetsu properly in whiskey peak yet he was showing off in loguetown
Then it’s revealed Zoro wasn’t even using any of his swords properly at all in Alabasta since he didn’t know how to not make them cut paper
Then the first attack Zoro uses with Shusui FAILS
Then Zoro FAILS to cut just a tree with Enma the first time
I mean does anyone else have “power ups” that work like this? Like Did Luffy use G2 and try to run but then overshoot because he wasn’t used to his own speed boost? Did Sanji get diable Jambe and his leg being on fire somehow made his regular kicking style unbalanced? No. No other “power ups” work like Zoro getting a new sword
In fact Zoro already has a “power up” like that, it’s 9 sword Ashura. That’s literally the only one that works like everyone else. It’s just a plain buff.
The difference between Zoro getting a new sword and everyone else is that Oda KNOWS that swords don’t just make you strong in that linear way. I mean Oda worked on Kenshin Himura. He must know something about real swordsmanship unless he wasn’t paying attention to what he was working on
Zoro is a skill fighter on top of being a power fighter. His abilities are way too tied to his skill level to be that linear. For example, if your logic was correct then what’s up with Tashigi. Tashigi collects swords. In fact she’s even collected swords that are BETTER than the sword she herself uses. She has Meito sword and yet one of the swords she collected from a pirate was a Wazimono. Tashigi is always complaining about being weak, why doesn’t she just use one of those better swords if “better sword = better swordsman” so linearly?