Could pecorino be used on nachos?

I can't imagine it would melt right and I'd worry about the saltiness of the cheese plus the saltiness of the chip would make for a real salt bomb. But who knows? Did you try it?

If that's the only cheese you've got on hand, go for it. But keep it mind it won't give the same melting effect as cheeses like cheddar, mozzarella or the like.
Maybe mix the grated pecorino with some mayo before spreading over the nacho platter and grilling, for greater smooth melt.
Or just sprinkle on top without grilling.