The policy failure may lead you to where the policy failed but that only indicates that the policy was badly formulated or dishonest or token or unfairly implemented, or a combination of these. Then there are the unmentionable and politically incorrect problems that arise from specific cultural and social problems in a community, which unfortunately are often connected to race (or religion or gender). These have to be addressed of course (drugs, prison, guns, single parent household, etc.) In some cases addressing poverty and education, and enforcing existing laws, will deal with these. But not always. And it is very easy to simply blame "systemic racism" for these. And that is the situation we have today. Under these circumstances it is in fact an easy way out of a situation where you dont want to address anything in an honest matter because it might require discussion of race. It becomes much easier to just blame the whole capitalist or patriarchal or white-controlled system.