Except Kaido was obviously holding back.
Kaido vs Yamato is completely misinterpreted because people take that at face value.
It's Yamato vs her father, the big baddie of the arc.
There's an emotional stake here.
Also the best moment to showcase how, despite everything, Yamato very much mimics Kaido's fighting style because she learned how to fight by getting her ass beat by him for years.
These stuff are almost never taken at face value.
But powerscalers don't have working brains.
It powerscalers were MtG players, they would be Gruul players.