But learning math/science encourages certain cognitive habits which are useful in practice. For most people, I expect that these cognitive habits are where the value of a math education lies.
As an example, in math, you often need to define a new object out of thin air, and then think about whether the definition is useful (e.g., let u=log(x), then rewrite the integral in terms of u and see if it gets you anywhere). I hypothesize that even after you've forgotten the math content, this cognitive habit (constructing a new mental object ex nihilo, thinking about whether it's useful, and perhaps giving it a name if it is useful) sticks with you, and contributes to general intelligence in other contexts.
I'm talking about people claiming that kids rolling cylinders down triangular blocks or dissecting frogs is vitally important to their education beyond the level of a broad liberal education.
Denying students educational support in understanding the flexible and general frameworks of mathematics that lead to the organization of human activity sharpens the division of labor and diminishes the possibilities for democratic engagement in the society's mode of production. The anti-math argument therefore appears to support a hierarchical Brave New World social structure because it advocates that we raise children to become functional assets rather than full participants in the economy.