Here is an interesting quote I found as I was reading several academic journal articles about foreign accents. This quote sheds a lot of light on the nature of accent discrimination in society. Society is becoming increasingly more tolerant, however, there is still a long way to go.
Accent serves as the first point of gatekeeping because we are forbidden, by law and social custom, and perhaps by a prevailing sense of what is morally and ethically right, from using race, ethnicity, homeland or economics more directly. We have no such compunctions about language, however. Thus, accent becomes a litmus test for exclusion, an excuse to turn away, to refuse to recognize the other. (p. 64)
Lippi-Green, R. (1997). English with an accent: Language, ideology, and discrimination in the United States. Routledge.