apple tv box vs apple ap

I've noticed that Apple TV box gives you bonus features on films that you do not get if you just use Apple TV app. However, like others, I have noticed that Apple TV box is not putting my HDR films in HDR, although Dolby Vision is fine. Recently, I bought Psycho. With Apple TV Box, just high definition, but with apple TV app, same TV (77 inch LG OLED), it is in HDR. Furthermore, Apple TV Box, while it categorizes films into 4k vs others, it does not say HDR in corner, although it says dolby vision. On Apple TV app, it does say HDR and Psycho looks ten times better. I am noticing all my HDR films like Casino, American Graffiti, and so many others, look more like HD on Apple TV Box but look great on Apple TV app. I only watch films now on Apple TV box when I want to hear directors commentary.