Definition of “racism” — A) prejudice, discrimination, or antagonism directed against someone of a different race based on the belief that one’s own race is superior, and/or B) a policy, system of government, etc., based upon or fostering such a doctrine.
In this country, in our culture, the only race that has ever successfully set up a system of government and implemented policies of discrimination based on the idea that their race is superior to others is white people. Therefore, the only race that can accurately be called “racist” (if we’re talking about a racist individual) is the white race. So yes, minorities get to call “racism”, but whites don’t.
You may be thinking of “bigot”. Anyone can be a bigot. However, a white woman correctly calling out a group of white men for disrespecting a woman of color — and this has happened over and over and over and over again — doesn’t make her a bigot, let alone a racist.