Finnish people in Finland and Japanese people in Japan also have “white privilege” in the way you’re talking about—they don’t suffer from whatever disadvantages are associated with being black in America. White Americans have the ordinary range of privileges and disadvantages of people in any country (some are richer, some are poorer, etc). If you trying to evaluate American educational culture and schools
in general, it makes sense to compare white people in the U.S. with Finnish people in Finland or Japanese people in Japan or non-immigrant French people in France. To the extent we have this data, Americans perform very well in such comparisons.
If what you say about racism, etc., is true, that is actually an argument against the cultural explanation. That would mean that educational underperformance compared to other countries is caused by internal racism in the U.S., not some anti-educational trend across American culture as a whole. If you somehow erased racism and brought everyone up to the scores of white Americans, then the U.S. would be right behind Japan in educational outcomes—even though the Americans care more about football than reading.
Also, only about 5 states have significantly more funding for white students once you consider federal funds. About twice as many have significantly more funding for black students: https://www.urban.org/sites/default/files/2022-10/Measuring%... (see page 22).