Maybe I am just really really clever, but I really don;t get the issue IN THEORY.
"believing and behaving as though a black person is always disadvantaged and a white person is always advantaged can create." I don';t believe that at all! I believe that a white person will always (so long as racism exists) have the advantage of being white over a black person (in a country like UK or USA). That a white person has privilege in one respect, and potentially a relatively small privilege at that, says nothing about the two people's "net privilege" position which could be massively in favour of the black person. It could even be the case that two teen girls want to become singers and the black teen has the privilege of better education, more stable family, more wealth, nicer area to grow up in, straight not gay like the white girl, AND because of the "urban" style of music they both make the music industry prefers the black teen. But I would still say that the white teen has white privilege, even if overall she is massively disadvantaged, and even if her white skin disadvantaged them in their music career.
IN PRACTICE, if a term is misunderstood regularly then the people using it need to think about the best way forward.
When I talk about racism I talk about it from the point of view of living in a majority white country, the UK. I would never presume to lecture African nations on racism!
White privilege is maybe another way of saying "does not risk suffering the racism that minorities tend to suffer". I cannot see the problem with the term unless you don't understand it or you don;t believe that racism exists.
I do think that the shift (especially from the left) should be massively towards addressing economic underprivilege, and if one addresses economic underprivilege in a society which protects people from racial discrimination under the law, then huge swathes of black lack of privilege would also fall away.
Believing that white privilege is a thing does not mean that to address the inequality one must approach target dragging ethnic minorities up or (worse) dragging white people down. I think that racial disadvantage is best addressed by doing things like makign higher education free for all, and such a policy also helps those people who struggle to comprehend how they have white privilege.