I think what Root is getting at is that they're not useful in your everyday life, even if you're working with mathematics. Sure they may have applications here and there, and maybe some famous mathematicians were once interested by its symmetry, but overall the useful applications are little. The Toshiba article is one. Magic squares in art and music? Lol? Anything is useful in art and music. Citing specific examples is a good way to provide evidence, but when you're trying to argue for wide use of something, it may work against you. For example, Pascal's Triangle is useful. I cite the example of binomial expansion. One say may say that's a specific example, but then I could list tons of places where binomial expansions are used.