Given that Luffy is using Kong Rifle and Kong Gun Gatling, and that Law is using Gamma Knife, I would guess that Kidd is also using his upper tier techniques.
Zoro on the other hand has been more impressive than Kidd while using at best mid tier techniques (Homurasaki, Rengoku Oni Giri and Flying Dragon: Fire Blaze) without hardening. Let alone all out Zoro > Kidd. A Santoryu Zoro that has just been warming up already seems to be the stronger combatant. Zoro's mid tier technique this chapter triggered Kaido's Oden PTSD. That's the only reaction to a Supernova attack that made it to the Spoilers. Given the information available, it seems Flying Dragon: Fire Blaze was more impactful than Slam Gibson.
Their performance vs Apoo already made me think Zoro was the more capable fighter, but this fight is making me suspect the gap was larger than I previously thought (I wouldn't be surprised if by the end of the fight I argue that Santoryu Zoro is considerably stronger than Kidd).
It appears that Zoro's performance gap with Kidd will only grow as he begins to use his upper tier techniques and hardening in future chapters.
@Haoshoku,
@LANJI CUCKSMOKE,
@HexBozoline,
@Light D Lamperouge,
@ReggieZoldyck21,
@rerere.