Not true based on what?
4.6x the raw power.
Forza Motorsport 7 without doubt with be 2160p at 60 fps locked on Scorpio.
You're comparing a card running games not directly optimized for it with a game built for the hardware and already runs 1080p 60 fps locked on current hardware.
Optimization isn't going to magically make up a 3TFLOP difference. (even a 1080 struggles to keep 4K/60 on some titles)
I'm all for the Scorpio and will be buying one of course. But if you think games will be 4K/60 you are on some powerful drugs.