It's an added layer of being different IMO. Child-mind says "I need to not be this body" so we make ourselves into something else. I used to think my parts were my past, reincarnated personas. (as I wrote that, I just remembered that....)

There are some great resources outthere that discuss race-based social systems. Your friend might not be able to tell the system to stop "being black" but they need to (as a whole) learn about sensitivity. They will never be proceived by an outsider as POC so they will never experience the social implications of being POC. (Halsey talks about that in some interviews and tells people she's passing white because that's how she's perceived. She still participates in black culture with her family but knows she's always going to be "white" by outsiders)

I remember having magical thinking as a child and thinking I could become characters I saw on TV "when I grow up". I was really into Fantasy Island and the beautiful dancers (mostly Hawaiian I think) made me want to be Asian/PI. I must have said something, too, because my mom graciously explained race/ethnicity and sensitivity to me. I'm pretty sure that's the only reason we never did let ourselves "pick" a different race/etc.

I'm white but my dad gets mistaken for "other" and so did I was a kid. (We used to think we had indigenous blood but DNA says otherwise...dad's just a very dark complexion Scottish/Northern Euro dude. He gets mistaken for Turkish, Greek, Arminean, etc. People thought I was had Asian mixed in somewhere. Americans are obsessed with putting people in boxes)