Many blacks are familiar with how people of their race get harrassed and even framed for crimes they did not commit solely because of their race. So they can identify with what Trump is going through. The George Whitmore case in NYC (during the Civil Rights era) comes to mind as well as the persecution of the Black Panther Party, for example. Trump now has some "street cred" so to speak.
Now I don't think we are seeing the blacks swing to the Republican Party by any stretch. This will be a Trump only phenomenon. So if the Republicans want to keep this black vote and even build on it for the future, they will need to drastically change their ways. The current crop of RINOS do not appeal to black males at all. We need more street-wise Republicans like Trump with some swagger and machismo.
Those ‘blacks’ who would vote for Trump are the ones with higher IQs and are solidly divorced from those who are a drag on society.
Those who have a zombie-like association with the Democrat Party will never change as they view this party as their magic lantern. As there are many of their race who hold positions in the Democrat Party, they feel comfortable with it. The fact that they’re being sucked deeper and deeper into the evil liberal vortex is an irrelevancy.