LU
” I don’t think the Gedolei Hador would disagree with him.”
This simply isnt factual (in a general sense). Gedolim often argue on the Mishna Berurua.
As for this specific example. There are Respectable ways of arguing with a Gadol of the stature of The CC. R’ Moshe does just that by mitigating the CC stament as alluded too by DY. While not blatantly arguing, he doesnt really add something that the CC didnt know and yet says the CC’ rule “He said that in circumstance X, the result will certainly (he uses the word “b’vadai”) be Y. Since X happened, Y must be true.” Doesnt always apply because Z.