@roger,
Whether a particular movie should be considered a classic or not, my point is that hundreds of movies from this era convey racist tropes. Is HBO going to stop showing them? Are historians going to write notices for them all?
Why not after all, a bit of historical context is always good to get.
But then there are the books, the paintings, the plays, the graphic novels... etc. etc.
In short, don’t blame this particular movie — Gone With The Wind — for an entire era.