The reason that the Black Community abandoned the Party that has done so much for them is simple. A large portion of the Black Community have their hand out, and those individuals know that the Dimocrats will put something in their open hand. In other words- it's a payoff!!
Bingo! This is precisely the reason. Black Americans have been sold the notion that nothing good is ever going to happen to them unless the government does it. They've literally becomes wards of the state. So, whomever promotes expansion of the state and state services, will get their support. This "slavish" support of the state and the statist party is literally a "plantation mentality" that is truly offensive and demeaning, considering the history of blacks in this nation.
The support for slavery reparations is a spinoff from this plantation mentality. Anyone who thinks that the US government, or the American people owe the descendents of slaves anything should go and read Lincoln's second inaugural address. They want money, but the freedom of slaves was paid for in the blood of people from both the north and south. 350,000 union soldiers alone gave their lives for Union and for the end of slavery -- the losses touched nearly every family in the nation. Why shouldn't white families ask for reparations from blacks for the loss of family members in the struggle which set the slaves free?
The kind of politics which the Democrat Party practices -- one that creates racial divisions, class envy, and dependence -- is criminal in my opinion. Thank God that many African Americans are freeing themselves from this plantation mentality, and it's no coincidence that these "emancipated blacks" are more aligned with the Republican Party.