I think he’s on the Sanji = Zoro train....
You're probably right.
Sanji and Zoro are both settling into high YC level at the same time. Only chronic Zoro overestimaters would feel insecure at this development.
Cook being able to do all the things Zoro did, namely overpowering Kaido's tornadoes, breaking through his scales, overpowering his Hell Hakkei, and giving Kaido a permanent scar, remain a hard sell for me personally. I just cannot fathom, for the sake of the argument that Cook and Zoro are equals, exactly how Cook would have been able to do all those without inducing the biggest PIS in the series. I mean, because Cook could hurt Queen, then they believe Cook can hurt Kaido? Mind boggling.
Or to a lesser extent, we saw that Cook couldn't overpower Doflamingo's Parasite back in Dressrosa, whereas Zoro overpowered Fujitora's gravity. These people probably argued that Cook could have overpowered Fujitora, too, back then, despite evidence to the contrary, smh.
P. S.
If the argument of those who believe them to be equals boils down to "Plot demands Zoro schooling Kaido, so if plot demands it, Cook can school Kaido, too", then no one can stop me from promoting "Usopp can scar Kaido, too, if plot demands it". Nonsensical, I know, but "plot demands it" is always nonsensical. That's why it's such a poor excuse.