To take an obvious example, I'm sure his friends thought he was a swell guy, but I don't think we need to revisit Hitler's ideas about the Jews. I don't think we need to give much serious thought to theories about moon landing hoaxes or theories about how the Earth is flat either, no matter how nice the people promulgating them may be. We are only given so much time on this Earth; I can think of better ways to spend it than seriously engaging with obvious claptrap.
Everyone I know (and know of) espouses obvious claptrap from time to time. If that is the sieve with which you denote undesirables to remove from your personal sphere, your circle either has a radius of 1 or you delude yourself about your detection abilities.
