Grandboy (selecting a game’s display language): What’s “English (UK)” and “English (US)” and why are they different?

Me: The UK version is the original English and the US version came afterwards.

Grandboy: So now everyone speaks US version, right?

Me: No, loads of people still speak the original English. That’s why you make me say “lever” instead of “lever” so I sound like your YouTube gamers.

Grandboy (adopting a posh attitude): “Oh, yessss, I’d looove a kish, lorvely”

Me: Yes, exactly, that’s how everyone sounds in England… (makes squinty eyes at the boy)