Whooo Cariana - so powerful, so eloquent, and so to the point --> " the entire book is como se dice…basura." - translation for those who did not study Spanish - the entire book is, how do you say... garbage.
Your post, like some of the others, relates to The Warmth of Other Suns. Isabel Wilkerson concludes at the end that the life of one of her main subjects, Ida Mae Gladney, was more successful than the other subject, Dr. Robert Foster. Foster attained wealth. Ida Mae did not. She lived a working class life and so did 2 out of her 3 children. Wilkerson said that Ida Mae achieved a "spiritual" success. I wonder whether anyone could say this about JAY-Z. You are so right to ask the question - how is 'black excellence' to be defined.
Your remarkable statement " we must view ourselves as excellent, because we are Black and for no other reason" reminds me of a line from an off, off, off Broadway play called Salt --> "How sacred it is to be a descendent of those who were never meant to survive".