I have a couple ShieldTVs (AndroidTV) that have worked for me for years. They have worked with streaming services as I needed, but the main use case for me is Jellyfin for movies/tv and a good YouTube client that filters ads out. The shield has done a good job of passing the correct audio stream to the receiver and it looks good. There have been a few issues here or there with some codecs, but if I fall back on Kodi it usually works.

I haven’t tried an AppleTV despite being a mostly Mac/iOS household. It is difficult to find out how well the Jellyfin clients work on it, and last I checked there was no “official” client, just pay-for apps that may or may not do what I need.