I am not arguing against crating....and yes, I believe that an aggressive dog needs limits for his protection and the other pups in the house...along with the human.
I happen to have helped a few biters through their issues and absolutely did use crates and/or separate rooms for them.
I will say however that some dogs cannot be crated and will injure themselves and/or DIE in a crate. One must always supervise and determine whether the dog is handling the situation. I once had someone apply for one of my foster pups who had separation anxiety....no clue why they wanted him because they had had one. That one had been put in a crate while they went out and he died....they said he was flailing about when they left, but that they were told that was the safest place for him.
Sounded like perhaps he needed medicine ... but certainly could not handle the crate. My son adopted one from me that flipped his wig in crates...it was awful. Nothing is ever etched in stone.