Replaced by black hispanics, who grew up playing baseball 12 months out of the year.
Most Hispanics playing aren’t black, they are Latino.
In any case, in 2012 the MLB was 63.9% white. That’s up from the all time low of 60.3% in 2004. In 2013 the NFL was 29.26% white. In 2012, 78% of all professional basketball players were US blacks.