The organic Netflix app on my Z9D definitely has DV with "more pop" than my ATV4K Netflix app with identical settings. At this point, I prefer the Z9D app to the ATV app. In order of preference for Netflix: (1) Z9D app for DV; (2) Roku Ultra app for HDR10; (3) ATV app for DV
Obviously, UHD disks on player are superior to any of the above.
Sony XBR75Z9D, Samsung 65F9000 , Yamaha CX-A5200 & Outlaw 770, Harmony Elite
Samsung K8500, OPPO 103-D, Genie 2 and C61Ks, Roku Ultra, ATV4K, FireTV Stick 4K, and Nvidia Shield TV Pro