The thing is you still reduced arrogance to technical correctness. However, what I was trying to get at was, what about cases where the technical correctness is just fine? If it's their attitude or hygiene or something else that you don't like, how do you tell them that?
I was trying to get at the same thing you just said, which is that, like you, most people would become uncomfortable providing feedback on at least some of these. Meaning that you would have to turn away these candidates without any concrete feedback. Now how do you imagine they'll react when they realize most people do get feedback but they didn't? Is their reaction (which might result in bad publicity) a risk you and your company really want to take? For what gain?
So the thing is, I think arrogance is typically reflected in actual deficiencies in interview performance. If it isn't - if it's just a vibe that the interviewer got with no concrete implications for how they work with others, solve problems, or communicate - then I worry taking it into account is introducing bias. If I can't think of a concrete implication that the arrogance had, then I don't think I want to take it into account. (You almost always can identify concrete effects, though.)
I was trying to get at the same thing you just said, which is that, like you, most people would become uncomfortable providing feedback on at least some of these. Meaning that you would have to turn away these candidates without any concrete feedback. Now how do you imagine they'll react when they realize most people do get feedback but they didn't? Is their reaction (which might result in bad publicity) a risk you and your company really want to take? For what gain?