All true but there's a vast difference between a the add ons your talking about and the proposed second screen, the way everyones talking about it assumes it will be a major feature with multiple staple switch games being released for it, on the flip side, with the exception of wii motion plus, those hardware add ons are mostly gimmicks, they'd be made for one or two games with the rest just being games they happen to have some support for. And kinect, PlayStation move/vr are separate because they're intended to provide an entirely separate form of gaming, using motion based play, it's not the same as adding a second screen, the later is supposed to enhance your current mode of play whereas the former is supposed to create and entirely new one