But to answer your actual question, that is often what the BBC or the show runners will fall back on -- this notion of "tradition" or "British culture."

It happened with Midsomer Murders, for Christ's sake.

And the best part is, like, guys, where do you think these Indians and black people came from? Oh, right, you enslaved them and brought them here. So how are they not part of British culture when you literally fought to ensure that they would be?