There are lots of versions of similar things that I haven't tried because I don't like a key ingredient - so for example I have never tried pickled onions, picked eggs, pickled gherkins, or kimchi.
I have also never tried whisky. I don't drink alcohol now at all but even when I did I couldn't stand the smell of whisky. There are no doubt lots of drinks I have never tried - both alcoholic (eg lots of liqueurs) and not (eg Irn Bru and Red Bull).
I eat meat but have never (knowingly) eaten horse. I have also never tried tripe, brains or pigs trotters (though I like some forms of offal). I have also never tried foie gras (but assume I would like it if I did).
I eat most fish and seafood, but have never tried jellied eels (or any other sort of eel) or cockles/winkles or rollmop herrings or kippers.
When it comes to fruit and vegetables, I don't think I have ever tried artichokes (either globe or Jerusalem) or jackfruit, but I can't think of anything else offhand. I haven't been actively avoiding these. Just haven't tried them.
No doubt there are lots of things not easily found in the UK, but I presume we're not counting those!