To be fair, his heroes were Lincoln and Forrest. He has said more than once Forrest was morally reprehensible, Foote admired his courage on the battlefield and his ability to lead men.
But yeah, I read the trilogy and noticed a general Southern bias. I don’t know if I’d go so far as Apologist.
Foote also seems to ignore that while NBF was a great cavalry raider, he was actually pretty crap as a commanding General, other than Brice’s Crossroads. Mind you, even I have to admit that the CSA Cavalry raiders were critical to the early successes, and NBF was one of the top three or even top two. Battle of Tupelo,Battle of Franklin, Third Battle of Murfreesboro, etc all showed he really only knew how to do one thing- but he did that one thing very well.