Kinda a follow up on this request for an AV1 software decoder in the Plex app, it looks like soon Android will have its own system-level AV1 decoder for video playback.
https://9to5google.com/2024/04/19/android-av1-software-decoder/
It would be good if Plex could utilize this in the future. Right now I can play back AV1 fine on my phone from my Jellyfin server when I use Findroid and its experimental mpv player engine, but not with the Plex app.