Any worthwhile scientific theory that has been substantiated creates a shift in human thinking. And it's happened time and time again without serious long-term resistence.
But when it goes on and on without substantiation, that isn't "hard to accept", that's just obduracy. And crying about how everyone hates me because I'm pretty, is not going to make the grade.
About 40 years ago, Jensenism was a minority theory among intelligence researchers, plausibly anyway, but it was for sure the popular target of hate, associated with everything evil and wrong. Arthur Jensen and his allies at the time were the targets of every type of popular backlash, including violent threats, roudy demonstrations, and blistering editorials, as though it was discovered that they preach doctrines of the KKK in their classrooms. What happened afterward, then, was a little unexpected: Arthur Jensen's arguments quietly and gradually won over the majority of intelligence researchers. The academics who intended to collect evidence to oppose him (such as Sandra Scarr and Robert Sternberg) instead collected evidence that confirmed his theory. Such evidence includes transracial adoption studies, brain size correlations, skin color correlations among populations, racial admixture correlations, and the same hierarchy existing in almost every multiracial society, all on top of the established knowledge of strong genetic heritibility of IQ within groups and genetic racial variations of many other phenotypes. However, the shift among intelligence researchers happened quietly, they did not much affect academic opinions outside their field, and the public remained completely oblivious to this shift, believing that the experts believed that racial variations in anything politically important was no more than pseudoscience. Why did the public remain oblivious to the academic shift? Because popular ideology affects which ideas are popularly aired. The Huffington Post or Salon or Washington Post or MSNBC or NPR may each have a hundred articles about the Flynn Effect or about the claimed non-existence of race or about the claimed uselessness of IQ, but only a few very-carefully-worded articles that acknowledge that the race-IQ gaps even exist, or that IQ variations are mostly heritable, or that IQ correlates with brain size, or that IQ has an 80% relationship to academic success and a 50% relationship to income. These are all established facts, but, if they are scarcely told to the public for fear that they are racist or elitist, then what do you expect the outcome will be? God help a newspaper editor if he or she publishes a full defense of Jensen's theory of race and intelligence. Millions of members of the public who perceive established science to be fringe was the result. This means, if a scientific theory is hard to accept because of the politics, then it matters, because the politics has a very strong effect on the perception of the probability of a theory. If you have decided ahead of time, before ever looking at the complete body of the evidence, that only a neo-Nazi would believe this ridiculous pseodoscientific bullshit, then... the evidence absolutely will never matter regardless.