Actually, I have no notion that our forbearers were illiterate.
But education was promoted by the founding fathers, especially Jefferson.
A large portion of America had no formal education, even during the Civil War Era and beyond. We, as a whole, were not literate. Many, many people could not read or write. The number of schools were very limited.
I will agree that government interference has been the demise of public school. That, imho, has been a fairly recent event. Had the system remained as it was intended, we wouldn’t be having this conversation.
Well, maybe we can get back to real education someday. But to the education thing back then, from what I know we were pretty literate, reading the Bible, conducting commerce, writing letters, etc. Why do you think we were not?