He doesn't understand math at all, not at K-12, college, graduate school, research, applications, etc. at all.

E.g., his claim about symbol manipulation is total nonsense.

His direction is a waste of time.

If he wants to improve materials for learning math, then fine, but he should first learn some math.

He should start with the books and papers of P. Halmos, one of the best writers of math ever.

Note: My Ph.D. dissertation research was on the math of stochastic optimal control.