People underrate the hell out of Kaido's speed, because he rarely dodges attacks, so it makes him look slow.
Kaido is hard to powerscale because he takes so many attacks because he's suicidal, and can't be bothered to care about most of them.
I think there were like 5-10 attacks on the rooftop that actually threatened Kaido's basic survival instincts that he decided to get the fuck out of the way. That's why I loved Luffy trolling him in that one panel, it was such a well-written moment, that you could tell REALLY pissed Kaido off because it hit home:
Lucci is fast as fuck, but Gear 5 was outspeeding full-power Kaido.