Videos of white tennis players berating umpires, smashing multiple rackets, threatening officials, and even hitting umpires with balls can easily be found online. There doesn’t seem to be any instance of mass-boycott to result from those players’ actions.
Consider the privilege of white tennis players like John McEnroe (who sides with Williams), whose abhorrent on-court behavior became an almost beloved signature in professional tennis. Compare that with the experience of Williams, arguably the best living tennis player on earth, who in 2018 must still face racist cartoons that depict her physique and features styled in the way Black people were drawn during the height of the Jim Crow era.
With the umpires threatening to boycott Williams’ future games, they are saying that although most (if not all) professional tennis players have had similar outbursts on the court, it’s particularly the outbursts of the greatest tennis player of all time — a Blackwoman — that are so damaging to their profession.