I believe there are two aspects to this situation.
One is the film itself, and the other is its screening in 2018.
First to the film.
Like every single piece of art, it was of its time, and attitudes have changed, a good thing, but that does not entitle people to airbrush history, and by that I mean the film, not the events it portrayed, o how specifically it conveyed them. For that reason, banning the film is not appropriate in my view.
As for the events portrayed - there is not a single film ever made concerning a true historical event that has not taken dramatic liberties for the sake of creating a more entertaining film. It could have been completely historically accurate, but then it would be a documentary for education, not a feature film for entertainment.
I don't believe that racism was in the minds of the film's creators, nor do I believe it comes over as having overt racist content in the finished film.
It was a piece of entertainment, written and filmed under the auspieces of attitudes at the time it was made - trying to airbrush it out of cultural history is inappropriate.
The historical accuracy of the film, or not, is irrelavent to the debate about its being shown.