You're kinda missing the point.
Kaguya only gets 4B vacuum fists
after absorbing IT chakra. Before absorbing IT chakra her vacuum fists are only 5-B.
The reason why her post IT absorption VF are 4-B is that her TSOs downscale from ETSO and we know Kaguyas vacuum fists scale above her TSO.
I recommend reading the thread where this was accepted if you still don't understand:
Greetings my friends, today I have cooked up a special meal with Samlex that has been long overdue in the wiki, this is going to be about Isshiki scaling massively above Kaguya's ETSO Energy Per Second value. I know there will be some inevitable misconstruction but regardless I urge everyone to...
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