How best to teach and effective teaching are problems solved long ago. It’s unaffordable for most.
What’s being discussed here is how to optimize mass education so that it’s least bad and is effective for a majority or least a substantial portion of children.
"It’s unaffordable for most."
Utter nonsense and the educational data says its nonsense. If what you say were true, the highest performers in STEM fields would be from the richest areas. In fact, the opposite is true, the majority of the highest performers come from middle of the road places. You are trying to make this about money. Its not about money. Its about the negative consequences of ideology and politics.