I think your comment does have value, its why I responded to it, to add context.
Racism and all *ism has an interesting (as in sociological) property that like electric charge is simulates the opposite charge on the other side of the dielectric. I happen to fall into the last unprotected class on the planet (old fat white guys :-) but having worked with and at times managed a very diverse set of folks my entire life it became clear there are people who are racists by 'choice' and people who are reflexively racist.
Lets postulate for the sake of example that racism had a measurable quantity, from 1.0 which is some sort of 'my race is the only one worth anything' to the 0.0 which is complete blindness to race in thought, speech, or action.
The perception of racism or sexism for people whom have discussed the experience with me was that one person could exhibit say 0.5 units of bias, and they they fall into a thought process that everyone is 0.5 racist. It very much shares a sort of 'herd immunity' reflex. If 90% percent of the folks in the group are blind to race issues then the 10% who aren't will stick out. What percentage of people have to be tolerably racist before its toxic? Does it matter? Why would anyone tolerate any sort racism in the work place?
So if person A is racist by choice, which is to say they have done some sort of evaluation and decided that race has an effect which transcends environment or skills, their actions and comments will create in people of that 'other' race a reflexive alter-racism (and always people are not perfect reflectors, for some it bounces off, for others it gets amplified). Now you get something like racism amplification by stimulated emission of insults [1} or something. That sort of situation is, painful, toxic to morale, and legally actionable.
The critical point though is we have to see this sort of missive not as 'professional victims' (although there are such people, painting any individual into that group without first hand knowledge is probably wrong) but as a signal that you have a problem. And getting everyone to buy into the notion that we're all individuals and not everyone finds ethnic jokes or sex jokes funny, is one of the more important jobs for management. As an individual you're best off trying not to be part of the problem.
[1] RASEI? The effect is remarkably similar