I mean, it's possible those people legitimately think those characters overshadowed T'Challa. Personally, I do think he needed more focus and I didn't need all those supporting characters but he was still by far the star of the show so I don't think he was at all overshadowed, so much as sometimes, not always, underserved by the narrative. And I didn't care much for Killmonger, because I thought T'Challa was more interesting by far, so that's another thing which varies between people.
Interesting. Maybe this'll give the game a boost.