People write about history through the lens of their specialty and personal interests, which is what the author of the underlying article was doing when they published in their academic journal, Southern Culture. The author has a lot of insight and foreknowledge into their field of expertise and can situate this story within that context better than others can, and more deeply (probably) than they could do in some other context.

It's pretty normal, and helps develop a lot of different perspectives on history so that the bigger picture can be understood in a lot of different ways.

It's fair to call it out, but it's not going anywhere and it's not really a problem in the writing. Taking this history and reconciling it with other accounts is a reader literacy thing.

You should take a similar eye to pretty much all history you run across.