You're not believing this are you?
He just got a durability power up, nothing power wise. Do you really think zoro is not strong enough to bypass his durability when he was strong enough to bypass kaidos? Delusion is strong with this one.
This is how One Piece works, Sanji unlocks something, edges out ahead of Zoro, then Zoro unlocks something and becomes stronger again.
Sanji was stronger with diable jambe until Zoro got Asura
Sanji was stronger after getting the raid suit until Zoro got Enma.
Now Sanji is temporarily stronger than Zoro until Zoro unleashes his new power up.
Stop this bullshit of course any character can "overcome" durability, but Sanji and Zoro would have an high to extreme diff fight before this new upgrade, and this gives Sanji much more leeway and stronger clash potential.
Just because you overcome Kaido's dura a few times (but still fail to knock him down or do significant damage to slow him down) doesn't mean you can one shot anyone even far less durable than him, see Zoro vs King, and Zoro vs whoever he fights seriously in the future, all of which will have less durability than Kaido but still be mid-high diff fights.