why do people think kashimos surehit is a oneshot KO?

we only see kashimo use his lightning on bums excluding hakari (hakari being someone that doesnt really know how to reinforce with the infinite CE he has in JP and has a bit more durability than normal in that state).

when he uses his lightning on sukuna w 1hp, half his reserves and brain damaged, sukuna survives since he can still transform into his TF state (meaning kashimos surehit didnt damage sukuna stomach housing CE or his head thats capable of RCT) if he did and it was a oneshot sukuna wouldnt be able to transform.

if you say kashimo purposefully avoided those places than thats a direct counter to his character as a whole and what we see. kashimo likes to finish things quickly and swiftly, if he could beat sukuna without MBA he would of, but he couldnt.

kashimos lightning isnt some end all be all, its a super concentrated action performed by him but if 1hp meguna can tank an EMW point blank and not get noticeably more beat up, chances are the normal laws of physics dont apply as much when dealing with high tiers.

im saying this because the people using in world physics to upscale kashimo is getting ridiculous, yes real EMW and electricity based powers would be OP in the real world but we see how CE negates those effects constantly.

anyways what are your thoughts? if you honestly believe his surehit is a oneshot for everyone even a full power sukuna then please provide solid proof and evidence, dont just say "nuh uh".