Hey, look, I'm not the engineer of the European oppression that created the modern racial identities (largely through shared experience of oppression, except White identity, which was created through shared experience as oppressors) and shaped most of the language around those identities. If you want to argue that the categories make no fundamental sense, you aren't wrong in their original delineation; they are groups of shared experience (which is also why even when the terms are the same or deeply etymologically linked, they have different concrete meaning in places where the historical experience worked differently; places, for instance, where the “one drop rule” [0] was a major historical force will, all other things being equal, have a far more expansive concept of “Blackness”.)

[0] https://en.m.wikipedia.org/wiki/One-drop_rule