Like Pres. Obama, VP Harris doesn't deny her heritage from either of her parents, but in many instances it's not up to the person how they identify—it's how the world sees them.
I love this quote from VP Harris...
“My mother understood very well that she was raising two Black daughters,” Harris wrote in her now-bestselling memoir “The Truths We Hold.” “She knew that her adopted homeland would see Maya and me as Black girls, and she was determined to make sure we would grow into confident, proud Black women.” That was before Harris attended a historically Black college and joined a Black sorority. (citation)
THIS is the reason many (smart) parents raise their bi- and multi-racial children as Black.
"Black" is how many bi- and multi-racial people will be seen and treated
based on their looks (every bi- and multi-racial person doesn't look like Halsey, Wentworth Miller or Derek Jeter and they don't have to worry about being "stopped and frisked" or driving while Black). The choice is based on common sense and not because of loyalty or commitment to one race or ethnicity.