My dad, who taught middle-school science through the 70s and 80s, put a lot of the blame for lousy math education on the elementary school teachers. He felt that well over 90% of them went into elementary education at least partly because they wanted to get a degree that didn’t require any serious math. Then as teachers, the major mathematical concept that they taught was that “Math is Hard”, because that was how they found it.
Of course, his opinion of a lot of the professors in the College of Education was even worse, but I’ll leave it here for now. To say the least, I am grateful that he coached me in math and helped me to enjoy it.