Oh no, the joke is, since England didn't change at all, there's no embarrassing fashion to blackmail him with BUT since America was always wearing what was "In fashion" at that time, England could blackmail him with his old fashion sense, because it's not fashionable anymore!
It's cool. Luckily I can't be blackmailed. I never kept up with the times~! Usually I'd wear a style of clothes for a while, then the world would start wearing that style and I'd be all "HELL NO!" and change into something else.