I think you've misunderstood my post. I'm happy that Lupita is in the film, I've said that many times already. I've clearly said I am fine with Lupita being the love interest, if that's what she'll be, I've said that already in a previous post. I do hope that the role she gets as a love interest is more than just shacking up with T'Challa, which is very possible. I have absolutely zero problems with black love in the big screen--I encourage it in fact, especially in the case of T'Challa--and I do hope that T'Challa does indeed get a black love interest, whether it is Lupita in the end or someone who even looks like her in someway, or someone else entirely. But they have to be black with no ambiguity. That has been my stance on the love interest role from the jump.
The reason why so many people are hoping Lupita would be Shuri instead is because damn near all of BP fandom has been fan-casting Lupita for the Shuri role for years now. Lupita is a great actress with a big name that many were hoping to play a super hero one day. It just so happens that there is a comic book character that is a highly-trained, highly-educated african warrior princess that becomes a "superhero" and even the Queen of her country and also happens to actually look like Lupita. That's Shuri in a nutshell. She's far more than just "background noise" in the comics, she actually is very important in it.
I also feel that under the right creative team, Shuri could def be Black Widow status, or even more. She def can be a character that black girls and black women in particular can absolutely look up to, the same way black boys and black men look up to T'Challa.
If Lupita is indeed the love interest, Monica Lynne or otherwise, then its all good. If so, I just hope that the love interest role will be impactful and will have a lot of meat to it.