Well, there are two and a half negatives to a larger iPhone that Apple haslong considered (1) bigger is harder to handle (2) a different size screen needs a different number of pixels, which is a pain in the neck for app developers.
The larger-than-life footage used to generate the window effect has been given its own bump, too, and the app can now handle 4K video as long as the Mac underneath (sorry, Windows folks) is powerful enough to drive it.