There is no new information here. It is known that many other gedolim disagreed with the Igros Moshe.
That other gedolim disagreed does not minimize his psak one bit.
His psak is chay vkayam and can be relied upon by every Yid.
The only one that can change the Igros Moshe’s psak is the Bal Igros Moshe himself.
I am concerned because I see some people trying to minimize the Kavod and Gadlus of Rav Moshe Feinstein ztsal because they have an agenda to disallow shavers.