As a hobbyist with no commercial reason that could justify faffing about with imported tapes, I have a deep hatred for import taxes and the (occasionally very) steep shipping prices across the Atlantic. If I'm gonna have to pony up 200% of the original price to get the tapes delivered to my doorstep, tape drives might as well be fictional to me.
Even in UK, you can buy them from Amazon Germany or from Amazon France, at only EUR 7 per TB for LTO-8 or around EUR 8 per TB for the older standards.
Previously there were no customs taxes but after Brexit I assume that there might be some taxes, but they should not be so high as to increase much this low price.