If the comic wants you to believe that then why does it include two black people who not only aren't acting like that, but balk at the idea of him acting like that? If the comic was trying to portray what you're saying it is, wouldn't they be happy about it and support it?
It's very obvious that it makes them uncomfortable and the butt of the joke is how dumb they think it is, not how totally black Foles is acting and how they totally love it. To say this is to ignore pretty much everything else the comic is telling you and to only focus on Foles.
It's much ado about nothing and I think too many people are trying to read way too hard into this comic when the joke is basically McCoy says all the talented players to leave the Eagles were black, Foles thinks he's black, Foles acts like idiot, everyone balks, the end.