I think that covers both transrace and transgender conversions.

I believe in that freedom, but also that white-to-black transracials may undermine the black liberation movement.

There is also a component to being Black that has a lot to do with actual lived history of our ancestors, and certainly no white-to-black transracial person can imitate that. Thus, the idea that one can fully opt into Blackness injures the Black racial memory.

In this case, we also feel (unnecessarily) lied to. Black people have no problem cheering on white people who pass the test. Rachel Dolezal could have been elected to the NAACP as an extraordinary white person. Instead, she selectively adopted the parts of blackness that she liked, and tried to ENFORCE that definition as real blackness (if you start to listen to the stories about her).