Exaggerate much?. I went to OU in the 80s, and my fraternity (founded in 1850) included Asian, Native American, Iranian, and Lebanese members. I did have a Hispanic pledge brother who didn't stick with it, but he was a bit of an oddball.
There were fraternities that weren’t racist, but there were ones that were. I went through the greek system at OU and OSU in the 80s and saw good and bad.