Earlier quoted context omitted.
Upvoted for American English The English tend to speak English better and have better grammar than Americans in my experience, but I do prefer American spelling (disclaimer: I'm American)
No. Like everyone else, Americans by definition speak their native language perfectly. There may very well be stylistic differences and you can aesthetically prefer a dialect, but native speakers do not commit grammatical errors.
There is a well recognized concept of mastering a language, you can claim (and I would agree) that dialects are respectable languages and AAVE is a proper English. Still some native speakers in any language cannot understand long sentences or know how to express complex information.
Otherwise if we go with the truism "everyone speaks their native language perfectly" we simply end up essentially saying that languages are fragmented to the level of individuals and that some language are inherently "better" than others. Both are positions I would not like were they to become mainstream.