I've looked at this a few times, and AppleTV actually has pretty poor support unless you're only using a select few streaming services and not streaming any of your own content.
Shield performs exponentially better in every way except for the god awful stock interface (and Google data collection vs Apple data collection).
The hardware and tvOS still have extremely limited support for most video codecs, no support at all for audio pass thru, and very limited non-stereo audio options. If you want the equivalent of watching on your laptop it's good, but if you have better than stereo speakers, or a 4K TV that supports HDR10+ or Dolby Vision, AppleTV can't compete except for the big name streaming services that have special tvOS privileges/integration.
FWIW, I have no trouble playing any of my alternatively sourced media, 4K Dolby Vision included, using an app called Infuse. Pass-through audio may indeed be an issue for some lossless surround formats, or at least that's what it sounded like the last I looked into it some years ago. I don't have the right room to set up surrounds so it's stereo only over here anyway. But that said I love the app, lovely interface, etc.
When I tried that before, the Infuse UI was unusably show for me, likely due to the library size, streaming from my server hung for a long time, it had to transcode most of the time because so few codecs were supported and it only supported stereo audio output. DV wasn't supported at all at the time.
It sounds like it's gotten better by a lot, but I'm curious whether you've had to pay for each newer version if Infuse. They were doing a "for life" purchase before, but that just meant the one major version number, and they were releasing new and EOL old major versions every 1.5-2 years at the time. It seemed like they were heading own the path of a monthly subscription payment model at the time
I had to look to remember, I'm on a $10/year subscription for "Pro". From looking at their page I'd say some codec support is under the Pro license. I know I haven't thrown anything at it that needed transcoding, but I'm not playing anything exotic either.
Being annual and pretty cheap I really don't mind throwing them some money to continue development, it's worth it to me for the experience. I can't tell from the website but I feel like there's a monthly option if ya just want to test the waters.
I stream all of my own content with an Apple TV and Plex just fine. I don't know what problems you've had there. It even handles exotic stuff like Hi10P h.264.
How's your surround sound? tvOS 26 decided at the last minute not to support audio pass thru, which means only the pretty basic audio codecs that the AppleTV itself can decode are supported. That's an extremely limited number, and I believe only the very basic 5.1 is supported for any surround options.
