People always overrated side characters in these movies. I don't know why that is, I think a huge part of it is the rise of amateur reviewers and it is easy to sound like you know what you are talking about when you go, "XYZ SIDE CHARACTER STOLE THE SHOW!!" Plus I think it is comic nerds just being excited a new comic character showed up.
And it ends up being 8 minutes of screentime, 7 minutes of it was action lol.
It happened with Black Panther in CW too... but at least he had a mini arc.
Okoye, Nakia, W'kabi, Killmonger had zero arc at all. They were the same from minute 1 to minute 120. M'baku had a mini arc, as much as you can have in 5 minutes lol. Which is fine... because they were all support character... supporting T'challa. Who actually changed throughout the movie. Because he was the main character.