“Y’all” and “got”??? Since when did Illinois become a Southern state? Since he’s lecturing, he should as least use “have” intead of “got”. Next, he’ll be speaking ebonics.
““Y’all” and “got”??? “ I believe that’s referred to as pandering.
The Great Migration that started in the 1920s (when Ford offered black workers the same wages as white in his factories) brought a lot of blacks from the South to Northern and Midwestern cities. They brought their dialects (and their cuisine, but that's another story) with them.
I don't see anything wrong with speaking colloquially on the stump, to reach people where they live. George W. Bush certainly does it, as did Bill Clinton. Hillary does it badly.