This is correct. The biggest reasons in purchasing a PS4 Pro is if you have a 4k/HDR TV or investing in PS VR. This is the reason why they're putting out this premium upgrade. HD TVs will barely notice any quality improvements.
I also feel that Scorpio will also cater to 4k/HDR and VR. I wouldn't be surprise if Oculus Rift 2 is released and HoloLens gains more marketing next year. This will fall in line with the mandate that Sony and Microsoft have said regarding games working on the existing as well as the premium. However, for premium owners of premium products like 4K TV output and Virtual Reality products, these systems will be noticeable.

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