There’s a lot of discussion on the bigger picture question, as to who is right: T’Challa or Killmonger. I humbly suggest the movie is making another point.

Quite bluntly, Killmonger just wants to reproduce the hierarchies of power, just with different people at the top. Which might be satisfying, and long overdue, but it’s not justice in the long term.

King T’Chaka chose to kill to keep Wakanda a secret and then lied, or lied by omission, about what happened. That lie poisoned a lot of the family tree.

Now, T’Challa seems to understand that in our age of surveillance, keeping Wakanda a secret is no longer possible. The end of Killmonger signals that T’Challa doesn’t want to replicate the hierarchies with someone else on top. T’Challa now has the chance to try something else, to interact with the world in an attempt to make it better.