Kaido was facing 5 monsters by his very own quote. Thats including Luffy, Zoro, Kidd, Law. Thats why he decided to go hybrid.
Oh and BM was not there? Kaidou went Hybrid after Luffy pummeled him in G4.
King was only facing Marco, Sanji and now Zoro and by the looks of it none of them were pushing him there even zoro until now.
Ok, since you think Zoro can perform as good as Luffy against Kaidou, let's see: Kaidou needs his Hybrid Form to fight
Base Luffy.
Zoro is using his 3 sword style with Enma and Bandana on, so he is in serious Mode.
Yet King doesn't need his Hybrid Form against Zoro even tho, based on your headcanon, he is as strong as Luffy.
And since you pay so much attention to who and when someone used their Hybrid Form to do biased powerscaling, following your Logic King is > Kaidou since he is fighting a serious Zoro who is as strong as Luffy, based on your opinion, while Kaidou needs his Hybrid Form to fight
Base Luffy.
A 85 to 100 doesn't make me power scale King into oblivion. Its just an accurate representation of the current circumstances.
Your headcanon is not a accurate representation.