The blacks and other nonwhites hate hate hate HATE white success in combat sports. For some of these groups the myth of physical superiority and masculinity is all they have, for others, they just hate the fact that white men can kick their ass.
They believe they are genetically entitled to fighting success and are naturally tougher and more masculine than whites, so they will call foul play whenever a white man wins.
It exposes a deep feeling of inadequacy and self-doubt in this myth within them.
Haney will not fight Lomachenko, he will not take the risk of humiliation because despite his machismo he knows what he is saying is not true.