Both exist mostly to disincentivize people from doing something immoral and/or unwanted, not to give light on the truth or false value of observations/evidence.
So the question is, should one really refuse to read/recommend ESR's book because of his opinions? Frankly, this smells to me like Index Librorum Prohibitorum all over again.
Unfortunately, you can't neatly compartmentalise one aspect of an individual's life and totally separate it from the others. Sometimes, the aspects with which you happen to agree might be used to indirectly (even invisibly) support the aspects you don't. Although it's difficult to judge that, it seems a reasonable condition for exercising caution. I say this as a huge fan of TAOUP.
So the question is, should one really refuse to read/recommend ESR's book because of his opinions? Frankly, this smells to me like Index Librorum Prohibitorum all over again.