Say the education system takes an input of children with a value of 1 and outputs educated people with a "value" between 5 and 10. Even if the system is overtly racist and only outputs minorities of values 5 and 6 it is still beneficial to everyone if the system is improved so that everyone gets a +1
Stop trying to put words in my mouth. I'm saying that the fact that a system produces unfair outcomes is not a reason to not make improvement that cause the system produce better outcomes across the board. No more, no less.