I pretty much never start such a wide-open thread, but I am curious about how certain others relate to me in this theme.
I bet those of us who consider ourselves very widely interested in foods and flavors--we're the opposite of picky eaters, if you will--still have certain flavors that somehow don't click for us. Of course, cilantro is well known for being repellent to some people because of genetic reasons. So we can maybe take that off the table as "solved."
For me, someone who truly relishes variety in foods, I can only think of two ingredients that just somehow seem wrong to me, unless done in a subtle way: tarragon and hazelnut. I can't even say that they taste bad, exactly, but that they seem "wrong" for me.
Any others out there like that? (I'd like to discourage replies from people who have a long laundry list of things they dislike, because that's getting into another question.)