People act like this a joke or republicans being stupid.
But it has a real effect
We form in-group/out group when very very young.
And while innperson contact is better, simply seeing other races on TV is enough to see a benefit.
Mississippi banned Sesame Street, and that made kids in Mississippi who set there in group/out group bias stricter along racial lines than if they had Sesame Street.
The people yelling about this stuff often don't understand why they're yelling.
But the people cutting the checks and driving the narrative believe in science and use it to their advantage.