The MCU and AP computer are part of a single module. The S/X do have a different MCU with a GPU and extra screen outputs. That may be shared with the Cybertruck and Semi.Really the Y vs S/X have different HW4 computers that odd. Different MCU makes sense but the camera module just seems like an off choice.
If that is the case they would only have two SKUs for the computer module. One for 3 and Y, and one for S, X, Cybertruck, and Semi.