And Luffy use jet gattling on Lucci and one shot him.
That's not how fights work in One Piece.
There was a massive gap, and to beat Kaku was a decent struggle for Zoro, (I'd say slightly moreso than Sanji beating Jyabura despite him coming into the fight with a bigger nerf). If it took all of Zoro's strength in some cases to lose clashes against Kaku, he is not beating someone with a better fruit, better martial arts skills and almost twice the base physical strength.
The data book had them maxed out on the scale, that just means the scale is bad.
I find this "nothing happened" feat to be wildly overblown by Zoro fanboys.
- Kuma was an ally and presumably he did not want to kill Zoro
- Plenty of characters who should have died don't die, it's One Piece
- Taking a TINY portion of the pain and damage that Luffy had been enduring without complaint was almost enough to knock him out.
- Luffy was bearing that pain and fought under those conditions, sleeping to recover, Zoro damn near died taking that pain on.
- Luffy recovered from more damage vs. Lucci very quickly and was fighting shape next arc, Zoro couldn't handle Luffy's recovery workload and was nerfed until the skip.
- Luffy's endurance/ recovery is very good, and better than Zoros.
All this to say:
Zoro isn't taking two Rokuougans to the chest better than Luffy took it.