You mean most amaratzim are repelled by the idea. They would feel the same with an uncle marrying a niece.
And a 90 year old man with a 13 year old girl… also perfectly fine l’halacha and yet would rate high on the “ick” factor of most people.
Just because a marriage is perfectly valid halachically doesn’t mean that it can’t “ick” one out. And just because it does, that doesn’t mean that s/he is an am haaretz.
The Wolf