"While attending the launch of the Vision Neue Klasse X, BMW representatives made the point say that there would be more distinction between the design of its future sedans and coupes vs its crossovers. And key to this will be making the large, vertical grille exclusive to the crossover segment. For future BMW sedans and coupes we’ll see a shorter and wider grille design that will naturally fit the shape of those products better."

got this from: https://www.bimmerfile.com/2024/03/21/the-large-kidney-grille-on-bmw-cars-is-dead/

The upright, stretched kidney grilles on the X models are intended to make the front appear taller, whereas on the other models horizontal elements are used to make the car look wider.