The sugar ruins it. Unless you're serving these with honey or jam, the sugar simply dominates. It doesn't seem like a lot, and a little sweetness is welcome in brioche or cornbread, but when I'm eating biscuits, I want the butter and buttermilk to shine. Baking is both science and art, so I don't know if it would still work without the sugar, but I'm happy with regular buttermilk biscuits, so I'll go with that.
