@mekkaokereke just as a data point i grew up in south mississippi in the 80s and 90s. for most of elementary school i was in catholic school and we learned about them there, though i can clearly remember one teacher in the fifth grade who insisted the civil war wasn’t about slavery (why it was important to make this point so forcefully to a fifth grader is another matter). they were taught in my public high school, but glossed over.
certainly the states’ rights myth was taught more vocally.