I disagree with much of that.
First, Kaepernick talks about racial injustice far more then economic injustice .. which is not the point of his protest. Talking about economic injustice, which is an entirely different subject, detracts from the real point of his argument. It doesn't matter how much money one makes, if you are black, the police may kill you because of it and for no other reason. THAT is the point.
A black company of any kind is not going have the same power behind the message as NIKE .. because NIKE is not a black company. What makes you think a message of civility and justice should only be spoken by black people?
Economic empowerment has nothing to do with the central issue .. and it only comes up now that Nike is in the game.
Your argument that it's better done by regular people than athletes again misses the point. Did LeBron open up a gymnasium, or did he open up a school? Do you think the only thing on the curriculum is basketball or sports?