That way of saying that the holocaust is a thing of its own, that can be compared to nothing else is simply a way of separating genocide victims into first-class and second-class victims. The only outcome would be to weaken the collective "Never again" outcry against barbary.
That's what they do in Germany. They teach it as a unique thing that can never happen again... which leads people to never question whether it could happen again... which may lead to it happening again, because any sign that it was happening again would be dismissed, because "it can't happen again" is drilled into people.
The default attitude of any human is to support the status quo, but you'd think Germany in particular would do a better job of changing that default with education. It seems like it doesn't.
Obviously, if someone was doing another holocaust, it would be in their best interests to make you think the very notion of more holocausts was prima facie completely absurd.
From the perspective of the victims, it was not special, indeed. My "research" focused on the other perspective to learn social patterns.