actually god isnt real isn't really responsive. a responsive arg would be "assuming/acting as if god is real is bad".
additionally, the evidence here is much more useful against authors like derrida, in which case the aff would not be extremely consistent with "god isnt real" [kinda the point of the strategy]
i cut these cards during lunchtime like two years ago and never thought about them again... but milbank is *most certainly* not a rationalist in any sense of the term. i think you are right that this card doesn't really say anything helpful though
edit: actually, I take that back. this card probably should just be merged with the one above it but certainly makes a card-worthy argument against rationalism/philosophies of pure reason, which definitely isn't the use of reason generally, but still indicts many strands of contemporary philosophy