Why isn't math taught historically and philosophically instead of arbitrarily throwing shit at the reader and just telling him "that's the way it is"?

Why was I simply GIVEN the number line for years as a young student, always wondering why it was important and why its inclusion seemed so arbitrary in my lessons, when five seconds of historical and theoretical context would have made me see how interesting and important it is? Why is math taught like a series of arbitrary operations and symbols to be memorized by rote, with no understanding of why they became conventional? Is this why most people on /sci/ are braindead retards who can't think outside whatever framework they've been brainwashed into during two years of study at Code Diaper University?