I think you're just illustrating the point. It's okay to address issues with racial bias in SAT questions. Those things can still be racist (maybe not even intentionally so) and worth addressing despite there being worse racism somewhere else. We don't have to ignore that, it's not getting diluted because there are neo nazis that exist somewhere else.
Using loaded terms like "racism" or "white supremacy" to describe major incidents as well as minor "not even intentionally so" infractions is pretty much the definition of dilution.
This conversation shows up on pretty much every HN story that ends up discussing racism. This fear of "dilution" is a textbook "no true Scotsman" fallacy.
