It does have a Roku app, but it’s very limited in features and barely developed. I tried playing some anime encoded with x265 and it was unwatchable for me because:

A. The TV could not handle the decode and there is no (sensible) way to force x264 transcoding on just the TV, and:

B. Selecting subtitles and audio tracks is painful and sometimes impossible. I tried changing my Jellyfin settings, my Roku settings, using the selectors on the episodes, even setting the default tracks in the video files. Nothing worked to have dual audio or dual subtitle files play the correct tracks.

I can’t speak for any other ecosystems, only Roku.