Native English Speakers: How do you feel about the American use of English?

For me personally when someone from U.K. speaks (and yes I’m from California, USA for reference!) it kind of sounds slang… Obviously I’m biased and trained to sound out 97% of the English spelling…

Or maybe I just have not heard proper English? (After all I do listen to a lot U.K. musicians talk perhaps they are using the cool slang)