User blog comment:Ghmorello/Chapter 923: In Soviet Russia, Dragon Rocks You/@comment-202.90.134.147-20181105075650/@comment-24850639-20181107191911

I don't think he was expecting someone Kaido's size to be able to move that fast. Even if he did foresee the attack to some extent, he clearly wasn't able to dodge in time. If this was just some vision of his haki, then we wouldn't have gotten the panel of Kaido saying what he said after wrecking him, or reactions from the townpeople of Luffy getting wrecked.

Also, there's nothing "unfair" about Luffy getting one-shotted here. You're seriously looking at this wrong if you treat this as a "slap to the face" to the people Luffy has overcome in the past. This feat is a testament to Kaido's strength, not a knock on the power level of other non-Yonko opponents. Kaido would absolutely destroy any of those people you mentioned, and he's supposed to, he's a freakin Yonko! Gear 4th was an absolute joke to be Big Mom, so why would it be any different against Kaido? The Yonko have been pirates for DECADES, facing off against all kinds of incredible opponents and constantly getting stronger. Luffy's barely got 3 years under his belt, and he spent 2 of them training because he saw that gap in power at Marineford. Luffy's timeskip training wasn't meant to put him on the level of the Yonko, and Rayleigh confirmed this when he said that he couldn't reach Katakuri-level observation haki with the duration of his training. This outcome makes perfect sense, and you guys need to let Luffy hold this L. It's how he bounces back from this that's more important. It's highly likely that he will close the gap before the arc ends, but you can't have seriously expected Luffy to be successful in this endeavor when the arc just started, and this was the first time we got to see Kaido fight.