Because "white" is now synonymous with evil. If you're white you're not allowed an opinion, success, wealth, or freedom. Some people tried so hard to eradicate racism that they became racist.
To be honest, I hope that these movements are a phase, and that once equality is somewhat established, people will stop being inverted racists and sexists
But I do, because I'm more righteous than you and I want you to know it
Romans 1:22