Have we all figured out a final answer to this yet? I'm getting ready to pull the trigger on a 75 inch Sony X900E 4k/HDR tv that does NOT support Dolby Vision. In this size / quality of tv I have to spend $1000 more to get a model that also supports Dolby Vision, not just HDR10. While essentially ALL UHD Blurays that support Dolby Vision also have a HDR10 version included, iTunes is labeling movies as either Dolby Vision, OR HDR10... non specifically show both. Considering most of the movies on iTunes with HDR, have DV listed I don't want to make a huge mistake and get a tv that doesn't support Dolby Vision IF that means I get NO HDR at all with many of the iTunes movies, on the other hand if they are defaulting back to HDR10 that is fine to me with current generation tvs in my price range.
This is difficult to say for sure without Apple explicitly saying so, test equipment, or Apple allowing 4K content download to inspect the file..
I have a Samsung KS9000 which is HDR10 only (HDR10+ after a update but moot point).
The main issue I have that makes it difficult to compare is the I can only get a good image when its calibrated for SDR
or HDR. So I can't quickly skip back and forth.
The second issue is the faux HDR. Even if I wasn't getting the HDR data from the Dolby Vision source that was mastered into the content would I be able to tell through the faux HDR?
Another interesting thing is Netflix auto detection for devices. If I set 4K SDR, close the app, restart the AppleTV, give it a second, it shows all the HDR content as "Ultra 4K". If I set 4K HDR 4:2:0 Chroma, close the app, restart the AppleTV, give it a second, it shows all the HDR content as HDR. Now if I set 4K HDR 4:2:2 Chroma, close the app blah blah....it shows all the HDR content as Dolby Vision.
Only thing I can say is when switching between the SmartTV Netflix app on content labeled HDR it looks identical to my AppleTV 4k Netflix app on the same content labeled Dolby Vision. Also when watching movies that are HDR and Dolby Vision from iTunes back to back they look to be comparable. So I can only assume, like others have mentioned Apple is using the HDR data shared with Dolby Vision.
As far as buying a TV, unless you absolutely need a TV you may want to wait until the Dolby Vision version drops. That way you get the best mastering of HDR content now and in the future.