[wrxtasy]

I m sorry but its NOT thats why i sold my Shield and bought an Apple Tv...
Have you checked Apple TV and NVidia Shield playing back 4K content in Kodi on the same TV side by side ? 

This doesn't apply if you are playing BT.2020 HDR content and the output is BT.709 SDR.

Getting away from all the Nerd speak, the core problem all along has been the Shield has had issues with colorspace conversion when switching from viewing BT.2020 (mostly used for 4K HDR) to BT.709 SDR
From my understanding SDR color output would be oversaturated unless you dug deep into settings all the time and manually set the correct SDR colorspace when viewing mixed HDR and then SDR content. Which ends up being a right royal PITA for long term usage for the average user.

It's also exactly why this thread was created:

Auto frame rate switching & dynamic range matching - 4K (HDR10) capable Hardware (click)

Basically users should trust their eyeballs and look out for oversaturation of color output with mixed HDR and SDR usage and color banding when watching 4K HDR content. Auto refresh switching on some platforms may add to the problems as well.

And we have not even started on the subject of 1080p > 4K picture upscaling quality yet. An issue that shows up the bigger and more expensive a display gets. Not just for Kodi but across the whole suite of Apps on 4K media players.