Mental state plays a big role in One Piece.
Katakuri can’t use Future Sight if he is not concentrated. Same way Kaido was having his Ptsd from the flashbacks of Oden and couldn’t concentrate, and we don’t even know Kaido’s backstory yet why he is suicidal.
Big Mom’s mental state was associated with Mother Caramel and she has problems due to her tragic past.
Shanks lost an arm to a Sea King despite his strenght and his overpowered Haki
Whitebeard got penetrated by Squard while off guard
Jozu blocked Mihawk’s attack and made Aokiji bleed
Physical prowess and Mental state are interconnected.
This is not the End
This is just Act-3 Real battle will start in Act-4, Act-3 always end in tragedy so wait for Scabbards utter defeat but if you think before that they don’t deserve anything, not even a scratch on Kaido then you are utter fools, this is their story and they are not like secondary characters of other arcs where they are just showpieces and the Straw Hats handle everything, in fact, we should be happy that we are getting competent secondary characters otherwise you guys would have a complaint that Oda is just doing the same thing.
When Kaido was introduced there was no mention that he can’t be injured it was mentioned he can’t be killed there is a vast difference.
As soon as Kaido sobered up he is fine and now fully ready to battle and if you can see there is no scar left on him except the Oden’s one. He is a monster and can heal quickly due to his powers.
*Theory by Sumit Tyagi