To be exact, American English is considered to be more archaic. They continued using the old spellings, which arguably were fluid at the time anyway. Examples are Mountain English, that use 'afeard' for what we call 'afraid' (see: Shakespeare)

Rotten BBC article: https://www.bbc.com/culture/article/20180207-how-americans-preserved-british-english

https://forums.digitalspy.com/discussion/1818966/is-american-english-in-fact-closer-to-true-english-than-british-english