Handy, I know it's easy to toss out the race card, but the D is presently dominated by NY and CA folks (see: AOC, Pelosi, Schumer, Schiff, Swalwell, et al). And those folks are far more liberal than Dixie-crats. Liberalization of the D is a real factor. But I'll give you credit by saying not the only factor.
In the end however, folks vote wallet even over (their most despicable) biases.
Don't believe me? Previously lily-white Kentucky basketball went integrated when they realized they could reach more fans (aka money).
Dixie-crats are fiscal pragmatists and don't see NY/CA liberalism in their fiscal favor.