Killmonger is a master class in economical character development. In less than 15 minutes of movie intro and later exposition, we learn everything we need to know about his motivations and how he became a villain. No need for a Killmonger trilogy following him through the mean streets, basic training and deployments, and his work for the CIA. (Now that I’ve said it, Disney is all but guaranteed to release that trilogy). He’s great because we get enough info about him to see the humanity in the villain while leaving the details to our imaginations.
That sounds…underwhelming. This is the sort of disappointing backstory I’m talking about. That sounds a lot less interesting than any backstory I can imagine to fill in the blanks.