While I mostly agree that the true punch of this gen has yet to be shown, watching some of the trailers in 4K makes it immediately apparent that they could not be rendered on any current gen console. Horizon: Forbidden West and Pragmata in particular.
Oh you misunderstand! I am not trying to imply that games like Horizon could run on a PS4. I am simply saying that the visual leap to the human eye is less impressive, even on my 4k TV. It has nothing to do with technical aspects that explain why a game could/could not run on a gen 8 machine, but more to do with the diminishing returns of visual leaps from gen to gen as a whole. I meant that it LOOKS like a sharper PS4 Pro game with a few added details that will go unnoticed in motion, not that the game could in fact run on a PS4.
Not to mention, with Horizon in particular, I am sure there are some new physics related things that will even further prevent it from being played on a gen 8 machine.