What evidence do we have that the SCOTUS decision to strike down portions of the voting rights act of 1965 was right or wrong?

In one decision the SCOTUS has declared that the need for southern states to get federal permission to change voting regulations is no longer needed because racism is not significant enough to necessitate the continuation of the Voting Rights Act of 1965 as we know it. This, in an era where voter suppression in southern states was obvious, seems to contradict reality. This, in an era where a TV personality on the food network uses the 'n' word when she described a party she would like to have and where the Confederate flag is flown proudly in southern states, seems incongruous.