It’s a non-profit. The board isn’t the same as as the supposed beneficiaries or target audience.
La Raza, now called UnidosUS, is a non-profit and Steyer’s wife was on a lot of boards, but she’s not on the board of UnidosUS now. Everybody on it has a Spanish last name (except one guy who looks Mexican), so I doubt she was ever on it. Maybe some group that she’s affiliated with works with them.