The ad in question is here.
To your last point, Brown Vs. The Board of Education prevents racial segregation in schools, Loving vs. Virginia prevents state laws against interracial marriages, and Atlanta Hotel Vs. The US was the landmark finding that upheld the legitimacy of the Civil Rights Act of 1964, specifically the clause that prevents businesses from discriminating based on protected classes.
So to answer your question at large, we DO have actual laws on the books that are supposed to protect historically targeted minorities, but at any moment these rogue malefactors could declare any one of those laws unconstitutional as they’ve shown they have NO regard for precedent.