Yes, but will the non-people-of-color learn a lesson from this?
Probably not...
Certainly not the type of non-white people that will attend that rally in the first place.
This is difficult. But shouldn't that be "the people of non-color"?
Of course, you raise a salient issue by using the words "non-people." It reminds one of unpersons, which, for those who wrote the instructions, may ultimately be the point.
If you are a non-person-of-color attending such an event, you are already so hollow that your epidermis is your entire substance with its depth measured in micron, yes, micron...
...I guess that also applies if you are a person-of-color.