While I think that it indeed is racist to exclude people from an event solely based on their ethnicity, I also think it is outrageous that she is thrown out over this. This has absolutely no bearing on her job as a professor and I think it is very important to guarantee the right of freedom of speech for people working in science in particular. They should immediately reinstate her (though I must stress, regarding her comment in the article: Yes, reverse racism does not exist, it is just plain racism).