Apples and oranges. Cage, along with the rest of the cast, walked out of a bad music video/Blaxploitation film (which is, fair enough, his origin) into a bad, go-nowhere comic... which really suffers in comparison to his portrayal in Bendis' Alias which was coming out at the same time, despite Luke's portrayal in the first few Alias issues being not so great either.
Barracuda walked out of a prison documentary into a good comic and scared the hell out of everyone by being the mother of all badasses and a criminal genius, subverting some stereotypes and turning the rest of them up to 11. Ennis has a decent track record of using a few elements of stereotypes to build his characters without relying on them exclusively, to the point where the biggest complaint I have about him (OK, on his "serious" stuff like MAX Punisher or Battlefields, not talking stuff like The Boys or MK Punisher which bug me in whole other ways I'm not getting in to) is that Americans just don't use "cunt" that often. A stereotype used well says "This character has a history"; used badly it says "This character is representative of Group X."
Anyway, I'm not saying Azzarello is racist at all, but if I had to judge by CAGE alone, it'd look bad for him. (I have disliked just about everything I've read by him, though. CAGE, first 100 Bullets trade, Batman: Broken City, Superman: For Tomorrow. But that's mostly because they were boring/pretentious.)