You were missing the entire thing because that’s not what the ruling was from SCOTUS. All it did was reiterate the current responsibility of the president that he is immune from some of his actions of his job function when acting within the purview of his official function. He Would not be granted immunity at all if he was doing something that broke the law or was acting on a personal nature
They didn’t change anything other than reiterate what the president is immune from, what he has always been immune from and when he is not immune from prosecution