The webpage is presented as a fairly comprehensive overview of "American Dialects", of which AAVE is one of the most widely-spoken. To gloss over it the way he has is criminal, especially because he's an academic. This is part-and-parcel of the way blackness is marginalized in and erased from the American record. Essentially, every chart on the page is missing a column. It does a major disservice to anyone who might happen upon the page and view it as a credible source regarding the way Americans speak. You might as well present an atlas with the lakes and ponds removed from each map.