If you want to talk about racism, you have to acknowledge that racism exists.
And that people of different races are affected by it differently.
Everyone is equal, and that’s an important starting point. But not everyone is treated equally, and that affects everything.
Including what it’s like for people to listen to you talk about racism. When you talk about racism, it matters what race you are. If you want to say worthwhile things, it’s important to acknowledge that. Don’t try to pretend that you can just decide that it doesn’t matter for the purposes of the conversation you want to have.
In particular, if you say “just pretend I’m purple,” that will usually be understood to mean “I’m white and I’m not interested in thinking about how my white privilege affects other people.”