There was no error there, maybe he doesn't know if class is a major factor in Scotland or Ireland? That could make sense since England as the center of power that class would be more of a factor there for dialects, but I am not sure.

Yes exactly in fact I was specifically thinking of my belief that class is signalled less strongly in many Scottish dialects. But the general concept of class being closely related to accent is something that people will instinctively understand throughout the whole of Britain (and probably Ireland too), even if it's not that big an effect in their own local dialect.

The great thing about LLMs is we don’t have to argue about language any more, a machine can do it for us. Here is is explained:

“The common country error in that statement is confusing “England” with the entire United Kingdom.

Explanation: • The statement says: “This is the case throughout England at least. Brits take this for granted…” • It singles out England but then generalizes to all Brits (which includes people from Scotland, Wales, and Northern Ireland—not just England). • This is a common error, especially among non-UK speakers, where England is incorrectly used to refer to the entire UK.”