Engaging with this as though it were made in good faith:
A white man might be threatened by a black man expressing their opinion for two reasons. First, the audacity of someone "inferior" daring to express their opinion assertively. That could be seen as threatening. Secondly (and probably more likely) the social conditioning that black people, but especially men, acting with anger are naturally dangerous. That is, someone may feel vastly more physically intimidated by a black man expressing the same opinion, with the same words, at the same volume level than a white woman.
Would a person complain to HR about that? Absolutely. Would HR respond? Depends on the company and the people.
