As companies are able to deliver cameras that improve digital noise and add more sophisticated features while simultaneously delivering the OPTION of higher resolution (don't forget, you don't have to shoot full size RAWs), why wouldn't they?
It's not an "OPTION". Selecting fewer pixels to save to storage doesn't make those pixels any larger on the sensor, or give them another stop or two of sensitivity. I don't need the ability map pixels 1:1 to billboards, but being able to shoot my son indoors without motion blur would be awesome. Screw 36 MP. Give me 12 with another stop or two of usable ISO / aperture instead.
Don't you think consumers would complain if they knew a technology was capable of 36mp but companies were only delivering 12? I, for one, am happy that 35mm cameras are beginning to reach the resolution of MF, at least in terms of sensor capability.
Would the same consumers eventually complain if, unlike the proles, they awakened and began to understood that diffraction is already making today's pixel densities worthless? Will nobody be satisfied until we hit DLA at f/2.8?