Does the world know that the Panther is dead?
Bucky, as the White Wolf, has a position of honor within Wakanda and it is surprising that no-one checked in on T'Challa. Sam gets new tech, courtesy of Wakanda; and I get it that Coogler treated the real-world reality of Boseman (not telling anyone) as part of the story.
But.....
I know I sound like one of those posters that complained incessantly about, "Where were the other Avengers" in any solo film.
Yeah, it is a nit-pick but maybe it is a signal that this makes a re-cast smoother without destroying the current story-lines.