The thing you miss is minato wiped out entire army's to in the blink of a eye( a god dam blink)
Imagine what madara did to the ally forces but just in a blink . And u people act like clones are not apart of his tool belt
minato defeated an army of iwa fodders, while the army of kabuto consists of:
Edo nagato
Edo Itachi
Edo Akatsuki
Edo Kages
Edo 7 swordmen
Edo Jinchuriki
Edo KKG shinobis ( Gari,Pakura, Haku..)
Edo Dan,Edo Asuma, Edo Chiyo, Edo Kimmimaru, Edo Hanzo, Edo Kyubi Brothers of the Cloud.
The biggest mistake minato could make is going BM, because than he is a bigger target.
So he will stay in KCM to be fast, but the army is too much. Every edo would regenerate after it took a blow, minato has to seal them instantly after he land a critical hit, which is impossible due to the army consists also of fast shinobis who won't stand there and doing nothing.
Nagato was able to react to the speed of KCM naruto and V2 Bee at the same time, while itachi also was able to keep up with KCM naruto in taijutsu.
There is also the 3 raikage, who can't be hurt by minatos arsenal, even a tailed beast bomb won't really finish him and than he is edo so he would regenerate.
Mu with fast jinton is a big threat when minato goes BM.
He can fly and sense minato.
Deidara could blow himself up while kabuto sacrifices Manda 2 ( bigger and more durable than manda) to survive the 10 kilometer blast radius.
The Clouds Demon Brothers can go V2 to gain speed, they would be a threat.
I haven't started with Kabutos arsenal when he is in Dragon sage mode, its a joke Minato looses badly, i can't believe minato fanboys could overrate him that much.