Only recently has Shuri been smarter than BP. That's MCU Shuri currently in the comics (they don't even need her), rather than 616 pre-Coates Shuri. Pre-Coates, Shuri was a brash, hot-headed, overachiever, wanting to prove she was worthy of the BP mantle. Hell, that really was the only reason she was created. The only other thing she being shown to possess was a gifted strategic mind, that was still being honed in the field of battle. MCU Shuri definitely doesn't need to be BP, nor should they go that route again.
How to even break down this ongoing enigma with Shuri without sounding abrasive...
There's a vocal minority of people who will always want and need Shuri to be BP... (maybe dike black girls, idk) because BP's love interest being a black woman is not enough, his body guard and 2nd best warrior in his country being a black woman not enough, his black sister
simply being the smartest human in the world... nope, not enough.They need to have the number 1 headband. I get it, so i ain't mad. But fuuuuuuuck that.
As you said, Shuri's problem in the comics is that her entire plot point was being under her brother's shadow. At the time, everybody loved T'Challa, Wakandan children thought he was a god, even Panther god Bast told T'Challa "Out of all the BP's ever, you my nygga. I don't really fukk with your sister tho". Literally said that. So Shuri's problem in and out of comics on some meta shyt is that her more popular brother is always more popular, but her existence is to replace him.
So Coogler had a solution for that: he made her a nerdy millennial who
can't fight (no contention for the throne) doesn't want to be BP (no contention for the throne) and prefers being in the lab with her Reed Richards genius that Coogler gifted her as a consolation prize. And yet, that vocal minority still wants her to contend for the throne despite Coogler revamping the character for the sole purpose of creating a co-existence where the siblings compliment each other as oppose to being in each other's way.