The problem started with the nation-wide establishment of compulsory attendance, compulsory funded, single-payer, socialist schooling. ( Mid-1800s to early 1900s).
At best, modern single-payer, compulsory, socialist schooling offered the students a generic and lukewarm Protestantism. What is the problem with this? Answer: Children risked learning to be lukewarm and generic about their faith. What does Christ do with the lukewarm? He spits them out of His mouth!
It only took a generation or two for the socialist government schools to move toward secularism. My grandmother ( born 1894) attended secular schools that nodded to God on occasion. It was inevitable that socialists (that have **always** control teacher training and curriculum development) would increasingly move toward the utter godlessness that children and taxpayers are now forced to establish in these pits of ignorance ( misnamed “schools”).
You’ve studied this I can see. So what’s the solution? Please give me hope.