This is a bit of tangent, but also the textbooks being softened to avoid teaching certain things to kids is a not a good thing. The most I have ever seen for historical events like the trail of tears in a textbook was in AP U.S. History in my junior year. It was maybe half a page, a page at most.
Anyway, what I'm saying is (which can sort of go with the other books being banned), history should not be censored because we cannot face the truth. If we leave out important historical details, people are going to make things up and we'll never know the truth; and like they always say, forgetting mistakes of the past will let us repeat them in the future.
History textbooks maybe don't need to go into "disgusting details" for younger children (such as elementary students), but they should not leave out large chunks just because there are things like racism, murder, etc.