It seems like some answer to the question in the thread title could be inferred from what has happened in the wake of the Supreme Court striking down parts of the Voting Rights Act in 2013. They removed the requirement that certain states had to get pre-authorization from the federal government before making changes involving voting policies, as a consequence of their prior history of racist voter disenfranchisement. Since then, most of those states have passed various laws which tend to disproportionately impact voting access for minorities. Some of the laws, like in N.C., were subsequently struck down
for being explicitly racist. Other cases involving disenfranchisement this year are
in the courts.
So, I surmise that if we overturned the Civil Rights Act we would see a similar pattern, with an increase in segregation of public accommodations in those states, as well as a return to outright discrimination in employment and other areas. It's conceivable that those trends might be less pronounced than with the VRA, because with voting rights some of the motivations are just partisan, rather than being explicitly racist, whereas no non-racist motivation really exists for re-instituting segregation or discrimination. But there's plenty of evidence for the existence of discrimination and prejudice even where the CRA makes it illegal, so you would expect at least some marginal increase if the CRA were overturned.
Obviously, all of this would hurt black people much worse than smug white liberals.