Your ridiculous. Mozart has 250 years on Chuck Berry. The Olympics have over 2700 years on Louis Armstrong.
I hope you created your profile as a joke.
We were talking about American culture, you seem a little confused about that.
You raised a valid question.
Unfortunately your dismissal of the influence of classical music shows that you are not serious about considering the answer.
African impact was certainly important in the development of American music and culture.
Without or with greatly lessened African influence, other factors that were present, or that might have replaced such influences would have led to a different development.
BUT, there would have been such development. YOu cannot look at the music of the early 1700s and assume that that would be the whole of the US music scene.