I've noticed this most strongly where X is drawn from {Spanish-speaking countries, anywhere in Asia, Russia}. I don't have enough data points to be sure how still-native Arabs treat stereotypes and non-politically-correct word choices. (I have a hunch they are relatively thick-skinned, plain-speaking, and don't have the same stereotyping/language taboos as Americans/anglophones have, but I could be wrong.)
Yes, having experienced discrimination as a minority immigrant community in the English-speaking world would be one plausible explanation for greater sensitivity among X-Americans than native-X. As would now being in a culture that assigns greater deference to those expressing 'group offense'. It's overdetermined!
It would make an interesting sociological study!