It's got a lot of heart, and the soundtrack is incredible. I think Oundan beats it in mechanics, but this goes down as one of the most memorable rhythm games I've ever played.
I finished it on Master mode too. Bee Jam Blues, what a nightmare!
ThreadDigitalfoundry: Sekiro: Shadows Die Twice - PS4 Pro first look
Just PS4 Pro at the event I'm afraid, and only with 1080p output selected. Possibly there's more in store with the 4K mode. It'd be unusual if it's ignored entirely.
But yes, X is the one to watch at launch. If it's only 1080p there (small chance), it should be the best at hitting 60fps.