People who don't live in the US won't be up-to-date with American slang, especially if they don't live in an English-speaking country. It means the country is

People who don't live in the US won't be up-to-date with American slang, especially if they don't live in an English-speaking country. It means the country is a shithole: "A very dirty, poor, and unpleasant place" [1]. Britain's infrastructure is noticeably decaying — potholed roads, buildings in a poor state of repair (let alone well-insulated etc), litter, old buses and trains, homeless people sleeping on the street. There's more of this the further one travels from London. [1] https://en.wiktionary.org/wiki/shithole https://en.wiktionary.org/wiki/shithole