The ruling on affirmative action will make is much harder for schools to use race as a deciding factor in selection and much easier for students to sue. Affirmative actions was killed by the ruling just like bans on gay marriage were not killed by the other rulings but it was a big nudge in that direction.
The changes to the voter rights act did nothing more than say you have sets the rules for all 50 states as the same and that the decision to require preapproval should be based on how a bunch of racist democrats (yes it was the democrats) behaved in 1975. Congress refused to update the measure because to many states outside the South would do worse than some southern on any rational measure of civil rights. Also if you are opposed to affirmative action you should be opposed to this law. In a an effort to maximize minority representation it not only allows but often requires that white votes be minimized and in affect silenced by gerrymandering them into oblivion.
So what all the rulings had in common was that they all pushed the nation in the direction of treating everyone more equally.