It makes sense because imagine using two fingers for a hard press as a way to go back to home screen instantly just with the force of two fingers solves the problem. MUCH better than hold press since it's instant and you feel feedback as if you touched a button. Imagine having the same screen size with more portability. iOS 7 hinted iPhone 6 Plus due to the swiping in the corners of safari webpages to go back or forth. 3D touch HINTS the iPhone 7 because the way you can hard press the screen and multitask without having to click on the home button to switch apps.