If anyone else is reading along, the throwaway account is also lying about this (shocker!)
You'll open link to find a website that does not at all claim math is racist, but instead claims that it has been unequally taught for years. Which makes complete sense, as the racial gap in Math attainment in the US isn't replicated in other countries -- in the UK GCSE Maths levels for black students hover around or slightly above those of white students.
And of course like all such claims nobody to actually answer for why something was on the list. Just a lot of fearmongering that works on people.