Wait until we get introduced to the real power of the WSS. There is a reason why Oda put him in the same class as Whitebeard and Shanks.
- Mihawk challenged all the powerful opponents until no one could challenge him, and he beat them all. He might have challenged Kaido or Big Mom. We don't know, but we know that Kaido lost seven times. That's a big number for a man who is believe to be the strongest creature in the world.
- Mihawk is not a yonko because he simply doesn't have a crew and large territories in the new world. Mihawk would not challenge Kaido alone. He will challenge him, the commenders, the F6, and all footsoldiers. Also, Mihawk is not even interested in becoming a yonko.
- Shanks used to be the only person Mihawk thought of as a real opponent, and Shanks has the potential to be the strongest character in One Piece. We don't know when Mihawk fought him, maybe he fought him when he was a yonko. And we don't even know who won.
- Zoro is the Vegeta, Killua, or Sasuke of One Piece. The second most popular character in the series. Mihawk is his endgame opponent. You gonna eat your words when we get introduced to Mihawk's true strength.
Mihawk>>Kaido>Big Mom.