The proponents of political correctness represent a vile threat to freedom in America. Its use is intended to muzzle our most important freedom, under a false guise that it is kind and benevolent. The commies used similar tactics to gain control and justify murdering millions.
IIRC, the Nazis of Skokie Illinois got more latitude.
A fraternity is a private organization; the First Amendment does not apply to SAE kicking out a chapter.