I had Europeans tell me they don’t like it because of the wintergreen flavor, and that reminds them I specifically of medicine (that some of their medicines are flavored with wintergreen.) I wish I could be more specific about which area of Europe, but I don’t remember who told me that.
I tolerate wintergreen, but it’s not a flavor I particularly like. That said, combined with vanilla and sassafras or sarsaparilla or licorice, I don’t mind it.
Dr. Pepper is not at all in the same category to me. That just tastes like cola flavored with almond extract and maybe a few other things. More comparable drinks might be Moxie, birch beer, and sarsaparilla soda.