Coogler said they were experimenting with taking out those scenes. He said:
“And we were just talking like, ‘Yeah, it’ll work without it, ’cause X, Y, and, Z … And I remember I came in early at 6am to watch, because I just wanted to watch it down before we tested it with the scenes out. And we pressed play on it, and I was watching it, and it was just the worst movie ever, you know what I’m saying?”
Having seen the film several times, I don’t think losing those scenes would have resulted in the “worst movie ever,” but your mileage may vary. Still, the Dora Milaje are the heart of Wakanda, and that speech from Ramonda is just gut wrenching. Watching her fight to keep something else (vibranium) from being taken from her by the leaders of the rest of the world was a perfect study of what grief can do to you, and she was completely justified in what she did. I say this without a political science degree or anything like that, but the sentiment stands.