>

yeah thats because splitscreen is insanely taxing on hardware, so its impossible to do outside of games like that   
i bet even nintendo has problems to do it - hence we get games like it takes two where you are both on the same screen
XBox Live killed split screen gaming. They demonstrated that you could sell two copies of a game and get both people to pay $50/year for the privilege of playing together. >

I don't think this is unpopular,  at least not from the consumer standpoint. >

Fr? I don't really hear many discussions about splitscreen online apart from Halo. >

nintendo >

Other than Mario Kart and SSBU? Can't think about much else. What else?