I don't know the actual stats but I would imagine that the number of black players in the English leagues is disproportionately high compared to the number of black people in the country.
So then, given that a traditional route into management is to have been a professional player, "do your badges" and then get a job in the lower leagues managing somebody shit, you would expect there to be far more black managers in the game.
So then, given that a traditional route into management is to have been a professional player, "do your badges" and then get a job in the lower leagues managing somebody shit, you would expect there to be far more black managers in the game.