WFRP, which is originally a home-grown English RPG, has many British tropes that make it different from D&D. That doesn’t mean that many British-run D&D games are more like WFRP - depends what you want from a game and you don’t always want grim peril and leprosy - but the tropes are influential and many groups will have played both. That’s also possibly true of Ars Magica, which was pretty popular here a decade or two ago.
Another mild difference will be the influential media. Nowadays these will be more similar in the US and U.K. (LotR films, GoT, anime, various fantasy novels and video games, Witcher, etc) but for instance, more older gamers in the UK will have grown up with Robin of Sherwood, a UK TV series that was very influential. Maybe more UK gamers will have read every Discworld book, that sort of thing.