The reason I believe he’ll take it is because it is great grade just like Wado and Enma, when he blackens the three of them they will each ascend to supreme grade rank while sandai would only become skillful grade. Why else would the sword be highlighted in front of Zoro and why else would he take immediate interest in the blade that’s apart of the same family as his sandai? The other reason is Gandhi having a blade that has the same exact cross guard as the two confirmed kitetsu’s, no other blade in the story have remotely similar guards, which leads me to believe it’s the supreme grade variant shodai. The point I’m making is that I believe Oda is making a clear emphasis on the kitetsu blades and will lead to an eventual encounter between bald gorosei and Zoro. There would certainly be fascinating sword/swordsman lore given to us within their exchange if this all comes true. It may even be possible that Zoro obtains shodai but idk if he’d have time to make it black, so defeating the supposed shodai wielder w an ascended nidai in his possession would be awesome imo.
tl;dr: I believe there is a kitetsu plot line that will lead Zoro to Gandhi and I also believe he will ascend three great grades to supreme rank through blackening. Plus Zoro is accustomed to wielding a kitetsu so I think he’ll feel right at home w it, just like w enma because he was already accustomed to Kozaburo blades.