I can easily imagine something like this in IRL. You are sitting in a circle of friends and someone proposes well argued and supported point in support of somet

I can easily imagine something like this in IRL. You are sitting in a circle of friends and someone proposes well argued and supported point in support of something very horrible. You avert your eyes, attempt to pretend that you haven't really heard that. Then change the topic. If this happens frequently enough, maybe next time you won't invite this person. Remember, "reasonable" is different for every person. And "well articulated" and "respectful" does not mean "reasonable".