I don’t believe the 2019(shiny 4670) Roku Ultra supported Dolby Atmos or Dolby Vision at all. The 2020(matte 4800) Roku Ultra supports Dolby Atmos and Dolby Vision and supports passthrough of audio signals. Dolby Atmos works for video services. Unfortunately, the Amazon Music, Apple Music and Tidal apps do not support Dolby Atmos tracks.
The Nvidia Shield Pro, if I remember correctly, can also do the second unfolding of Tidal MQA that caps at 96/24 when other streamers will do 48/24. I swear I got it to work when I had it. I really need to get one, again. But, just as sure as I do, they will release a new model.