I think it is because the Party hasn't changed all that much. White Democrats still assume that black people aren't smart enough to figure out how to obtain an ID, skilled enough to get a job, intelligent enough to compete in an even playing field, or capable of making up their own minds about anything. Just as the plantation owners 150 years ago feared and hated any black slave who learned to read and write, and dared to offer an opinion about anything, white Democrats today hate any black person who doesn't allow the largely white leadership of the Democrat Party do their thinking for them. Yeah, the overall environment in which they live has changed, but white Democrats are still convinced that black people are dependent upon them, and very much want to keep them dependent. Their nominee for president couldn't have made that clearer when he said that someone isn't really black unless they vote Democrat, and you can see that in the absolute hatred they display against any black person who dares look elsewhere.