Black people mostly live in the South of the U.S before the great migration with rest living in large cities. I'm assuming you aren't American.
But neither Mississipi nor Lousisiana are majority black, not even close. Both are around 55-58% white and only 31-36% black. Georgia and Alabama are not much different. So there is definitely no "automatically MUST be black" requirement for the setting.
Now if this game is specifically about Creole mythology with all the Haitian and African influences then a black lead would fit, though I'd say a mixed race, much like the VO actress they hired, would be even better. Though digging deeper, they had a different mo-cap actress, Nona Parker Johnson, who IS from Mississippi and looks much more like the MC, for at least some of the work.
Anyway, the marketing for this just says "Deep South" which is not, as far as I, a life long Southerner, am aware is a code for anything other than just the more southern, primarily gulf states though Georgia and SC are sometimes put in there as well, off the Mason-Dixon line. It doesn't specifically mean voodoo or whatnot, so there can certainly be plenty of white people involved in this story and it still be 100% authentic to the region.
Since it is on GP its an easy play. I'll wait to see how much SBI taint is in there before I give it a go, but juuuuuust from the visual aspect it does look pretty cool if that frame rate jank can be turned off. But if it gets preachy (and everything suggests it will be) then its DOA as far as I'm concerned.