Recent cases like the ones in Atlanta, New Orleans, and Minessota are pretty clear that racial profiling still happens. Other cases that make it clear are the New York police chief who was pulled over and other similar people who fit a vague discription or were simply detained for being black in an unusual place.
Racism has decreased over the last century. Many people still harbor prejudice despite this movement toward a socially progressive nation, however. The Republican party in particular not infrequently expresses racist viewpoints, generally implicitly but sometimes, in the example of Donald Trump, explicitly. If elected officials are prejudiced, how can the country they represent not be?
The unfortunate practice of racial profiling, or automatically making arrests of individuals who are not white, cannot be brushed under the rug as something that "used" to happen. It continues to be an issue in America because it has resulted in far too many instances when young, innocent black men have been murdered by white police officers.
Racial profiling is still a huge problem because many people in the United States form split-second judgments about black men, Arabs, and other groups of people based on race. The recent shooting of black men by police officers has put the problem of racial profiling in the spot light once again, and proven it's continued existence.