Obviously it’s silly, but let me play devil’s advocate. They played the film this month, and there was a poor response from audiences. Audiences didn’t want to see it next year, so they swapped it out - the reason why is almost secondary.
As to that reason why, ever since I first saw it when I was a kid, the film’s glorification of the antebellum South bothered me. It’s of course a classic, and it needs to be seen, but there are other ways to see it. Let me put it this way: if it played at my local theater, I’d skip it and wait till the next screening.