Kaido carried this forum on his back
IMO the New World had 3 Major "Evil" Forces, and things are in limbo since they're all down right now.
1. Doffy
2. Big Mom
3. Kaido
Doflamingo took up two arcs, Big Mom took up Zou then Whole Cake then self inserted into Wano, and Kaido got the longest arc of the series, after being teased all the way back in Thriller Bark.
These three characters pretty much were the New World in terms of enemy fights. The vast majority of meaningful fights that the Straw Hats have had in the New World were against these forces (keep in mind Fish-Man Island is NOT in the New World, it's under the Red Line).
Until Oda fully commits to Teach as the new Big Bad Pirate, things are going to continue to feel a little rudderless.
Thankfully, since Imu is making his move, I guarantee Teach is, as well.
We'll see Kaido and Linlin again in the Pluton War.