The definition of the word "racism" is the following:
"1. the belief that all members of each race possess characteristics, abilities, or qualities specific to that race, especially so as to distinguish it as inferior or superior to another race or races."
To judge whether or not people are racists, one has to look at their intention and not simply judge their actions and behaviour alone, because racism is based on a person's intention to denigrate others, racism cannot be determined simply by judging the words they wrote in a dissertation.
Jason Richwine's dissertation was to explain whether or not certain groups of people would be compatible or incompatible for American society and its economy.
Being analytical about different races' compatibility for living in American society does not make the person a racist that is obsessed with denigrating other races of people.
Jason was perceiving the incompatibility/compatibility of different races for living in American society in his dissertation, no one except him can know whether or not he had any intention to denigrate those races.
For people to simply assume that Jason had the intention to denigrate those races without evidence(of his true intentions) and to perceive him as being racist and a bigot is simply being unfair, over-assuming, immature and perhaps blame-shifting as well.