BMW has a tradition to bring the exhaust of top-end from last generation as low-end in current gen. An example can be 520d/530i F10 with one-side, rounded exhaust to 520d/530i G30 double-sided one with trapezoid-like ends, that looked similar to 550i F10 models (at least in M-sport package).
I would expect new 7er will be act the same here: base model will have exhaust similar to the current M760li. At least to me, that makes sense.
IMO those small features, that today allows you to distinguish top-end model from base model will be one of the selling points for us, the owners, to switch. While owning high-end model, you don't want to be mistaken with newer base model by random bystanders, right
