The goal of these types of programs is to change cultures. If under-representation isn't caused by biology, then it's caused by culture. If the programs didn't target people within the cultures they're trying to change, they wouldn't succeed. They'd be full of the people who are already likely to be interested in programming, which isn't a problem in itself, but isn't the goal of the programs.
What if under-representation is caused by collectivism? After all, the solution to slavery wasn't reversing or evening out the ethnicities of slave and master, it was getting rid of slavery altogether.