Interesting controversy. If the idea of "soul food" has any meaning, then it can't be inappropriate for Black History month.
On the other hand, it is such a stereotype, I can see why people might be upset. Anyway, a kerfuffle. Make sure and watch the short video by the cook who chose the menu that day.
Some interesting background, on a MLK day menu, and history.
"Elon James White, on the timely, "Look, I really like watermelon. But don't offer me any" question..." (I like the part where Elon admits he is afraid of Melissa Harris Lacewell, a friend of mine, and a fine Duke PhD). (And, I had to watch the whole TWIB video twice. It is extremely funny. You'll see.)
As for the issue: It's complicated.
(Nod to Angry Alex)