He misrepresented the article. It does not claim that racism 'explains everything', merely that it was one of a number of factors which have led to the demonisation of MSG. That was a disingenous attempt to erase the effects of racism through ridicule.
The article provides no evidence that racism had anything to do with it. It links to a social history "study" which simply asserts it based on the existence of racism. It is disengenous to assume racism when there is no evidence of it being a causal factor.
Additionally, the implication in the comment I replied to was that the commentor must have hidden motivations, probably racist ones, for denying the influence of racism. That is a piece of obnoxious mind-reading that stifles reasonable dialogue.
