9% is in line with the proportion of blacks in the general population. If the black athletes with skills in 2 sports choose against baseball, there's nothing to be done there. I'm no expert, but my guess is that it takes a long time to get to big money in baseball. A star basketball player very rapidly gets to the big paydays. Ditto in football. The free market is working in its mysterious ways.
Yes, college football and college basketball are revenue sports almost everywhere. College baseball makes money at some schools although at many others it does not.