In the spirit of finding names for things, I thought this was interesting:
Moral dumbfounding occurs when people stubbornly maintain a moral judgement, even though they can provide no reason to support their judgements.Source
It typically manifests as a state of confusion or puzzlement coupled with (a) an admission of not having reasons or (b) the use of unsupported declarations (“It’s just wrong!”) as justification for a judgement, particularly when people encounter taboo behaviors that do not result in any harm.
The classic and most commonly cited example involves an act of consensual incest between a brother and sister with the use of contraceptive. Another example involves an act of cannibalism with a body that is already dead and is due to be incinerated the next day
The whole article is long but fascinating.