Is it complete BS, absolutely. But at the core of it, we're talking about people delineating groups based on sameness and otherness which is a practice as old as there have been social structures.
It helps kids to identify with a mentor whose shoes they can envision being in directly. More important than "looking like" though is feeling a sense of kinship that comes from similar background. I'm a firm believer that we should focus on the level of privilege not color. There are all types of people coming from a disadvantaged background that need help, how do we make programming/startups attainable and "sexy?" Silicon Valley's got that down but NYC is still a "banking city"