Not British, but taking UK out of the definition of pop, is a bit too rough a cut. Also France. Look at the queues outside pop-glamorous stores. And was pop-art a pop artefact? Is TikTok redefining pop? Movies is an old measure, and even US has fallen with just franchise dominating. I think as a globe we are much more integrated and co-dependent, occasionally also in bad ways, than we appreciate.