The problem with originalism is when you combine it with textualism, you straight jacket Constitutional interpretation, which is exactly what Scalia intended.
The argument is otherwise you have to guess the intent of the Founding Fathers, and it becomes a contest of historical cherry picking. But that's EXACTLY what Judges do, weight the evidence and come to a reasoned conclusion. So the text of the document is merely one piece of evidence, the intent of those who wrote that text (and it is a "they" not an "it") is also evidence that should be considered, as well as the compromises needed to enact the text.
So it's not just what the Founding Fathers wrote, it is their intent as well as the intent of the state ratifying conventions which made that text into higher law.
This still limits the range of interpretation, the idea of a "living constitution" is an oxymoron, the purpose of a Constitution is to bind future generations - if it is infinitely malleable to the fashion of the times it no longer binds and is not a Constitution. The amendment process serves to provide flexibility when the document becomes outdated, but only when there is a social consensus that change is required.