On some real shit.
Kaido beats Blackbeard at high-extreme diff.
BB has no way to hurt Kaido.
Once he makes him lose his DF abilities, he's still left with this dude
The guy that can speed blitz normal Luffy, and graze Future Sight Luffy.
He is in his prime and strongest age.
Kaido fucks Teech up so bad. Especially since Teech is arrogant and Kaido is a monster.
Teech only picks off those in their weakest stage.
Thats why he attacked Whitebeard, Garp, and Sengoku cuz he thought they were fodder.
If he was real tough shit he woulda went for Akainu or Kizaru.