From a linguistic perspective, this is probably backwards. American English tends to be more linguistically conservative than British English, and has changed less in the few hundred years since the divergence. This is a giant oversimplification, as it's much more nuanced than that, and there's not really one American and one British English.

It's actually not a bad comparison to Chinese, though, where Traditional Chinese is usually used in Hong Kong and Taiwan, but Simplified Chinese is usually used in mainland China.¹

@CriticalCupcake@tech.lgbt