The timing may be anecdotal, but since around the time when the Apple Silicon server version was released, the Apple TV software became really slow in loading any content from the server (M1 Mac Mini)
This happens on both the 4k Apple TV and the Previous 1080 version.
This includes showing Libraries or the Home display, opening a show, a film of a series, or even scrolling within the UI.
Any other device (Fire TV, Plex on iPad, Mac Web View or iPhone is perfectly responsive.)
This on top of the fact that the Apple TV 4K shows subtitles despite them not being switched on which is unfixed after more than 2 months (Apple TV App Won’t Stop Showing Subtitles) leads me to wonder if the Apple TV is getting a decent amount of attention.