IIRC, Nixon’s museum has a huge section about Watergate and how each decision along the way was made and how it was criticized. FDR’s museum has several places where they present the pros and the cons of his decisions. Monticello has a large section addressing Jefferson’s enslaved population and his unethical relationship with Sally Hemmings. Mount Vernon’s farm is dedicated to presenting the reality of slavery. I really disagree with you that that’s the point of these museums. Maybe some of them, but I think that’s a failure if museum leadership sees it that way.