I suppose, but that has nothing to do with tangs "needing" huge tanks. Rather, you could say, "while this fish could survive in a sixty gallon tank, it would be best to give it more space in the future, and doing so may help it avoid stress or disease and live longer". Doesn't that sound like a vastly more helpful response?
I will say it again: belitting people on the grounds of your unfounded beliefs will not help the person nor the fish one bit. Not at all. Believe me, I have experience on this one.